From 0888a63fbd4736cbcccc4cb9af4b9af3fefa94a7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E2=80=9Cpikachu28?= <“anjalisinghgsm@“gmail.com>
Date: Mon, 7 Dec 2020 19:12:35 +0530
Subject: [PATCH 1/5] Week_1 Solution

---
 Week1/Count Negative Nos/Anjali_Singh.cpp     | 15 +++++++++
 Week1/Count and Say/Anjali_Singh.cpp          | 18 ++++++++++
 .../Anjali_Singh.cpp                          | 24 ++++++++++++++
 Week1/Max Subarray/Anjali_Singh.cpp           | 17 ++++++++++
 Week1/Missing no/Anjali_Singh.cpp             | 14 ++++++++
 Week1/Monotonic Array/Anjali_Singh.cpp        | 20 +++++++++++
 Week1/Move Zeroes/Anjali_Singh.cpp            | 12 +++++++
 Week1/Pascal Triangle/Anjali_Singh.cpp        | 15 +++++++++
 Week1/Pivot Index/Anjali_Singh.cpp            | 28 ++++++++++++++++
 Week1/Product Of Array/Anjali_Singh.cpp       | 20 +++++++++++
 Week1/Remove Duplicates/Anjali_Singh.cpp      | 20 +++++++++++
 Week1/Reverse Only Letters/Anjali_Singh.cpp   | 21 ++++++++++++
 Week1/Reverse vowels/Anjali_Singh.cpp         | 29 ++++++++++++++++
 Week1/Rotate Array/Anjali_Singh.cpp           | 22 +++++++++++++
 Week1/Spiral Matrix/Anjali_Singh.cpp          | 33 +++++++++++++++++++
 Week1/Target Array/Anjali_Singh.cpp           | 13 ++++++++
 Week1/Valid Palindrome/Anjali_Singh.cpp       | 25 ++++++++++++++
 Week1/Xor operation/Anjali_Singh.cpp          | 15 +++++++++
 18 files changed, 361 insertions(+)
 create mode 100644 Week1/Count Negative Nos/Anjali_Singh.cpp
 create mode 100644 Week1/Count and Say/Anjali_Singh.cpp
 create mode 100644 Week1/Longest Substring wo repeating chars/Anjali_Singh.cpp
 create mode 100644 Week1/Max Subarray/Anjali_Singh.cpp
 create mode 100644 Week1/Missing no/Anjali_Singh.cpp
 create mode 100644 Week1/Monotonic Array/Anjali_Singh.cpp
 create mode 100644 Week1/Move Zeroes/Anjali_Singh.cpp
 create mode 100644 Week1/Pascal Triangle/Anjali_Singh.cpp
 create mode 100644 Week1/Pivot Index/Anjali_Singh.cpp
 create mode 100644 Week1/Product Of Array/Anjali_Singh.cpp
 create mode 100644 Week1/Remove Duplicates/Anjali_Singh.cpp
 create mode 100644 Week1/Reverse Only Letters/Anjali_Singh.cpp
 create mode 100644 Week1/Reverse vowels/Anjali_Singh.cpp
 create mode 100644 Week1/Rotate Array/Anjali_Singh.cpp
 create mode 100644 Week1/Spiral Matrix/Anjali_Singh.cpp
 create mode 100644 Week1/Target Array/Anjali_Singh.cpp
 create mode 100644 Week1/Valid Palindrome/Anjali_Singh.cpp
 create mode 100644 Week1/Xor operation/Anjali_Singh.cpp

diff --git a/Week1/Count Negative Nos/Anjali_Singh.cpp b/Week1/Count Negative Nos/Anjali_Singh.cpp
new file mode 100644
index 0000000..a70ad65
--- /dev/null
+++ b/Week1/Count Negative Nos/Anjali_Singh.cpp	
@@ -0,0 +1,15 @@
+class Solution {
+public:
+    int countNegatives(vector<vector<int>>& grid) {
+        int r=grid.size(), c=grid[0].size();
+        int count=0;
+        for(int i=0; i<r; i++){
+            for(int j=0; j<c; j++){
+                if(grid[i][j]<0){
+                    count++;
+                }
+            }
+        }
+        return count;
+    }
+};
diff --git a/Week1/Count and Say/Anjali_Singh.cpp b/Week1/Count and Say/Anjali_Singh.cpp
new file mode 100644
index 0000000..5490a85
--- /dev/null
+++ b/Week1/Count and Say/Anjali_Singh.cpp	
@@ -0,0 +1,18 @@
+class Solution {
+public:
+    string countAndSay(int n) {
+        if(n==1)
+            return "1";
+
+        string res;
+        string pres = countAndSay(n-1);
+        int start = 0, i = 1;
+        for( ; i<pres.size(); i++ ){
+            if( pres[i]!=pres[i-1] ){
+                res += to_string(i-start) + pres[i-1];
+                start = i;
+            }
+        }
+        return res + to_string(i-start) + pres[i-1];
+    }
+};
diff --git a/Week1/Longest Substring wo repeating chars/Anjali_Singh.cpp b/Week1/Longest Substring wo repeating chars/Anjali_Singh.cpp
new file mode 100644
index 0000000..9c0afb4
--- /dev/null
+++ b/Week1/Longest Substring wo repeating chars/Anjali_Singh.cpp	
@@ -0,0 +1,24 @@
+class Solution {
+public:
+    int lengthOfLongestSubstring(string s) {
+        int res=0,n=s.size(),left=0;
+        unordered_map<char,int>mymap;
+        for(int i=0; i<n ;++i){
+            if(mymap.find(s[i])==mymap.end()){
+                mymap[s[i]]=i;
+            }
+            else{
+                if(mymap[s[i]]>=left){
+                    left=mymap[s[i]]+1;
+                    mymap[s[i]]=i;
+
+                }
+                else{
+                    mymap[s[i]]=i;
+                }
+            }
+            res=max(res,i-left+1);
+        }
+        return res;
+    }
+};
diff --git a/Week1/Max Subarray/Anjali_Singh.cpp b/Week1/Max Subarray/Anjali_Singh.cpp
new file mode 100644
index 0000000..12c679b
--- /dev/null
+++ b/Week1/Max Subarray/Anjali_Singh.cpp	
@@ -0,0 +1,17 @@
+class Solution {
+public:
+    int maxSubArray(vector<int>& nums) {
+        int sum=0, maxSum=INT_MIN;
+        for(int i=0; i<nums.size(); i++){
+            sum += nums[i];
+            if(sum>maxSum){
+                maxSum=sum;
+            }
+            if(sum<0){
+                sum=0;
+            }
+        }
+        return maxSum;
+
+        }
+};
diff --git a/Week1/Missing no/Anjali_Singh.cpp b/Week1/Missing no/Anjali_Singh.cpp
new file mode 100644
index 0000000..1431e5c
--- /dev/null
+++ b/Week1/Missing no/Anjali_Singh.cpp	
@@ -0,0 +1,14 @@
+class Solution {
+public:
+    int missingNumber(vector<int>& nums) {
+		sort(nums.begin(),nums.end());
+        cout<<nums.back();
+		if(nums[0]!=0) return 0;
+		for(int i=1;i<nums.size();i++){
+			if(nums[i]-nums[i-1]!=1){
+				return i;
+			}
+		}
+		return nums.back()+1;
+    }
+};
diff --git a/Week1/Monotonic Array/Anjali_Singh.cpp b/Week1/Monotonic Array/Anjali_Singh.cpp
new file mode 100644
index 0000000..a03be7f
--- /dev/null
+++ b/Week1/Monotonic Array/Anjali_Singh.cpp	
@@ -0,0 +1,20 @@
+class Solution {
+public:
+    bool isMonotonic(vector<int>& A) {
+        int len = A.size();
+        int count1 = 1;
+        int count2 = 1;
+        for(int i = 1; i < len; i++){
+            if(A[i] >= A[i-1]){
+                count1++;
+                }
+            if(A[i] <= A[i-1]){
+                count2++;
+                }
+        }
+        if(count1 == len or count2 == len){
+            return true;
+    }
+        return false;
+    }
+};
diff --git a/Week1/Move Zeroes/Anjali_Singh.cpp b/Week1/Move Zeroes/Anjali_Singh.cpp
new file mode 100644
index 0000000..6440564
--- /dev/null
+++ b/Week1/Move Zeroes/Anjali_Singh.cpp	
@@ -0,0 +1,12 @@
+class Solution {
+public:
+    void moveZeroes(vector<int>& nums) {
+        for(int i=0, j=0; i<nums.size(); i++){
+                if(nums[i]!=0){
+                    cout<<nums[j]<<" "<<nums[i]<<endl;
+                    swap(nums[j++], nums[i]);
+
+            }
+        }
+    }
+};
diff --git a/Week1/Pascal Triangle/Anjali_Singh.cpp b/Week1/Pascal Triangle/Anjali_Singh.cpp
new file mode 100644
index 0000000..2a879ff
--- /dev/null
+++ b/Week1/Pascal Triangle/Anjali_Singh.cpp	
@@ -0,0 +1,15 @@
+class Solution {
+public:
+    vector<vector<int>> generate(int numRows) {
+        vector<vector<int>>ans;
+        for(int i=0;i<numRows;i++){
+            // make i+1 copies of 1 in row
+            vector<int>row(i+1,1);
+            for(int j=1;j<i;j++){
+                row[j] = ans[i-1][j] + ans[i-1][j-1];
+            }
+            ans.push_back(row);
+        }
+        return ans;
+    }
+};
diff --git a/Week1/Pivot Index/Anjali_Singh.cpp b/Week1/Pivot Index/Anjali_Singh.cpp
new file mode 100644
index 0000000..e67caa2
--- /dev/null
+++ b/Week1/Pivot Index/Anjali_Singh.cpp	
@@ -0,0 +1,28 @@
+class Solution {
+public:
+    int pivotIndex(vector<int>& nums) {
+        int leftSum=0, rightSum=0, sum=0;
+        for(int i=0; i<nums.size(); i++){
+            sum += nums[i];
+
+        }
+        if(nums.size()!=0){
+        rightSum = sum - nums[0];
+        if(leftSum==rightSum){
+            return 0;
+        }
+        }
+        rightSum = 0;
+        for(int i=1; i<nums.size(); i++){
+            leftSum = leftSum + nums[i-1];
+            rightSum = sum -nums[i]-leftSum;
+            cout<<rightSum;
+            if(leftSum==rightSum){
+                return i;
+            }
+        }
+        return -1;
+
+
+    }
+};
diff --git a/Week1/Product Of Array/Anjali_Singh.cpp b/Week1/Product Of Array/Anjali_Singh.cpp
new file mode 100644
index 0000000..ec50ab0
--- /dev/null
+++ b/Week1/Product Of Array/Anjali_Singh.cpp	
@@ -0,0 +1,20 @@
+class Solution {
+public:
+    vector<int> productExceptSelf(vector<int>& nums) {
+        vector<int> left(nums.size()), right(nums.size());
+        left[0] = 1;
+        right[nums.size()-1] = 1;
+        for(int i=1; i<nums.size(); i++){
+            left[i] = left[i-1]*nums[i-1];
+        }
+
+        for(int i=nums.size()-2; i>=0; i--){
+            right[i] = right[i+1]*nums[i+1];
+        }
+        for(int i=0; i<nums.size(); i++){
+            left[i] = left[i]*right[i];
+        }
+
+        return left;
+    }
+};
diff --git a/Week1/Remove Duplicates/Anjali_Singh.cpp b/Week1/Remove Duplicates/Anjali_Singh.cpp
new file mode 100644
index 0000000..146f2d4
--- /dev/null
+++ b/Week1/Remove Duplicates/Anjali_Singh.cpp	
@@ -0,0 +1,20 @@
+class Solution {
+public:
+    int removeDuplicates(vector<int>& nums) {
+        int n = nums.size();
+        if(n==0||n==1){
+            return n;
+        }
+    int temp[n];
+    int j = 0;
+    for (int i=0; i<n-1; i++)
+        if (nums[i] != nums[i+1])
+            temp[j++] = nums[i];
+    temp[j++] = nums[n-1];
+
+    for (int i=0; i<j; i++)
+        nums[i] = temp[i];
+    return j;
+
+    }
+};
diff --git a/Week1/Reverse Only Letters/Anjali_Singh.cpp b/Week1/Reverse Only Letters/Anjali_Singh.cpp
new file mode 100644
index 0000000..707ff50
--- /dev/null
+++ b/Week1/Reverse Only Letters/Anjali_Singh.cpp	
@@ -0,0 +1,21 @@
+class Solution {
+public:
+    string reverseOnlyLetters(string S) {
+        int l=0, r=S.size()-1;
+        while(l<r){
+            if(!isalpha(S[l])){
+                l++;
+            }
+            else if(!isalpha(S[r])){
+                r--;
+            }
+            else{
+                swap(S[l], S[r]);
+                l++;
+                r--;
+            }
+        }
+        return S;
+
+    }
+};
diff --git a/Week1/Reverse vowels/Anjali_Singh.cpp b/Week1/Reverse vowels/Anjali_Singh.cpp
new file mode 100644
index 0000000..bd9af71
--- /dev/null
+++ b/Week1/Reverse vowels/Anjali_Singh.cpp	
@@ -0,0 +1,29 @@
+class Solution {
+public:
+    bool isVowel(char i){
+        i = tolower(i);
+        if(i=='a'||i=='e'||i=='i'||i=='u'||i=='o'){
+            return true;
+        }
+        return false;
+
+    }
+    string reverseVowels(string s) {
+        int l=0, r=s.size()-1;
+        while(l<r){
+            if(!isVowel(s[l])){
+                l++;
+            }
+            else if(!isVowel(s[r])){
+                r--;
+            }
+            else if(isVowel(s[l])&&isVowel(s[r])){
+                swap(s[l], s[r]);
+                l++;
+                r--;
+            }
+
+        }
+        return s;
+    }
+};
diff --git a/Week1/Rotate Array/Anjali_Singh.cpp b/Week1/Rotate Array/Anjali_Singh.cpp
new file mode 100644
index 0000000..e90f0f1
--- /dev/null
+++ b/Week1/Rotate Array/Anjali_Singh.cpp	
@@ -0,0 +1,22 @@
+class Solution {
+public:
+    void rotate(vector<int>& nums, int k) {
+    //     while(k!=0){
+    //         int j = nums[nums.size()-1];
+    //     for(int i=nums.size()-1; i>0; i--){
+    //         nums[i] = nums[i-1];
+    //     }
+    //         nums[0] = j;
+    //         k--;
+    // }
+        int n=nums.size();
+        int a[n];
+        for(int i=0; i<n; i++){
+            a[(i+k)%n] = nums[i];
+        }
+        for(int i=0; i<n; i++){
+            nums[i] = a[i];
+        }
+
+    }
+};
diff --git a/Week1/Spiral Matrix/Anjali_Singh.cpp b/Week1/Spiral Matrix/Anjali_Singh.cpp
new file mode 100644
index 0000000..f0a3064
--- /dev/null
+++ b/Week1/Spiral Matrix/Anjali_Singh.cpp	
@@ -0,0 +1,33 @@
+class Solution {
+public:
+    vector<int> spiralOrder(vector<vector<int>>& matrix) {
+        int r=matrix.size(), c=matrix[0].size();
+        vector<int> ans;
+        int k=0, l=0;
+        while(k<r && l<c){
+        for(int i=l; i<c; i++){
+            ans.push_back(matrix[k][i]);
+        }
+        k++;
+        for(int i=k; i<r; i++){
+            ans.push_back(matrix[i][c-1]);
+
+        }
+        c--;
+        if(k<r){
+        for(int i=c-1; i>=l; i--){
+            ans.push_back(matrix[r-1][i]);
+        }
+            r--;
+        }
+        if(l<c){
+        for(int i=r-1; i>=k; i--){
+            ans.push_back(matrix[i][l]);
+        }
+        l++;
+        }
+        }
+
+        return ans;
+    }
+};
diff --git a/Week1/Target Array/Anjali_Singh.cpp b/Week1/Target Array/Anjali_Singh.cpp
new file mode 100644
index 0000000..835ce56
--- /dev/null
+++ b/Week1/Target Array/Anjali_Singh.cpp	
@@ -0,0 +1,13 @@
+class Solution {
+public:
+    vector<int> createTargetArray(vector<int>& nums, vector<int>& index) {
+        vector<int>ans;
+        for(int i=0; i<nums.size();i++){
+            //insert() is a built-in function in C++ STL which inserts new elements before the element at the specified position, effectively increasing the container size by the number of elements inserted.
+            //To avoid overwriting in the array/vector
+            ans.insert(ans.begin()+index[i], nums[i]);
+        }
+        return ans;
+
+    }
+};
diff --git a/Week1/Valid Palindrome/Anjali_Singh.cpp b/Week1/Valid Palindrome/Anjali_Singh.cpp
new file mode 100644
index 0000000..b8f9924
--- /dev/null
+++ b/Week1/Valid Palindrome/Anjali_Singh.cpp	
@@ -0,0 +1,25 @@
+class Solution {
+public:
+    bool isPalindrome(string s) {
+        transform(s.begin(), s.end(), s.begin(), ::tolower);
+        int l=0, r=s.size()-1;
+        while(l<r){
+            if((!isalpha(s[l]))&&(!isdigit(s[l]))){
+                l++;
+            }
+            else if((!isalpha(s[r]))&&(!isdigit(s[r]))){
+                r--;
+            }
+
+            else if(s[l]==s[r]){
+            l++;
+            r--;
+          }
+            else{
+                return false;
+            }
+    }
+
+        return true;
+    }
+};
diff --git a/Week1/Xor operation/Anjali_Singh.cpp b/Week1/Xor operation/Anjali_Singh.cpp
new file mode 100644
index 0000000..b64720e
--- /dev/null
+++ b/Week1/Xor operation/Anjali_Singh.cpp	
@@ -0,0 +1,15 @@
+class Solution {
+public:
+    int xorOperation(int n, int start) {
+        vector<int> x;
+        int a=start, s;
+        for(int i=0; i<n; i++){
+            s = start + 2*i;
+            x.push_back(s);
+        }
+        for(int i=1; i<x.size(); i++){
+            a ^= x[i];
+        }
+        return a;
+    }
+};

From 118807092712fcdd1eb82dab54207c0fef749e01 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E2=80=9Cpikachu28?= <“anjalisinghgsm@“gmail.com>
Date: Mon, 7 Dec 2020 19:13:57 +0530
Subject: [PATCH 2/5] Revert "Week_1 Solution"

This reverts commit 0888a63fbd4736cbcccc4cb9af4b9af3fefa94a7.
---
 Week1/Count Negative Nos/Anjali_Singh.cpp     | 15 ---------
 Week1/Count and Say/Anjali_Singh.cpp          | 18 ----------
 .../Anjali_Singh.cpp                          | 24 --------------
 Week1/Max Subarray/Anjali_Singh.cpp           | 17 ----------
 Week1/Missing no/Anjali_Singh.cpp             | 14 --------
 Week1/Monotonic Array/Anjali_Singh.cpp        | 20 -----------
 Week1/Move Zeroes/Anjali_Singh.cpp            | 12 -------
 Week1/Pascal Triangle/Anjali_Singh.cpp        | 15 ---------
 Week1/Pivot Index/Anjali_Singh.cpp            | 28 ----------------
 Week1/Product Of Array/Anjali_Singh.cpp       | 20 -----------
 Week1/Remove Duplicates/Anjali_Singh.cpp      | 20 -----------
 Week1/Reverse Only Letters/Anjali_Singh.cpp   | 21 ------------
 Week1/Reverse vowels/Anjali_Singh.cpp         | 29 ----------------
 Week1/Rotate Array/Anjali_Singh.cpp           | 22 -------------
 Week1/Spiral Matrix/Anjali_Singh.cpp          | 33 -------------------
 Week1/Target Array/Anjali_Singh.cpp           | 13 --------
 Week1/Valid Palindrome/Anjali_Singh.cpp       | 25 --------------
 Week1/Xor operation/Anjali_Singh.cpp          | 15 ---------
 18 files changed, 361 deletions(-)
 delete mode 100644 Week1/Count Negative Nos/Anjali_Singh.cpp
 delete mode 100644 Week1/Count and Say/Anjali_Singh.cpp
 delete mode 100644 Week1/Longest Substring wo repeating chars/Anjali_Singh.cpp
 delete mode 100644 Week1/Max Subarray/Anjali_Singh.cpp
 delete mode 100644 Week1/Missing no/Anjali_Singh.cpp
 delete mode 100644 Week1/Monotonic Array/Anjali_Singh.cpp
 delete mode 100644 Week1/Move Zeroes/Anjali_Singh.cpp
 delete mode 100644 Week1/Pascal Triangle/Anjali_Singh.cpp
 delete mode 100644 Week1/Pivot Index/Anjali_Singh.cpp
 delete mode 100644 Week1/Product Of Array/Anjali_Singh.cpp
 delete mode 100644 Week1/Remove Duplicates/Anjali_Singh.cpp
 delete mode 100644 Week1/Reverse Only Letters/Anjali_Singh.cpp
 delete mode 100644 Week1/Reverse vowels/Anjali_Singh.cpp
 delete mode 100644 Week1/Rotate Array/Anjali_Singh.cpp
 delete mode 100644 Week1/Spiral Matrix/Anjali_Singh.cpp
 delete mode 100644 Week1/Target Array/Anjali_Singh.cpp
 delete mode 100644 Week1/Valid Palindrome/Anjali_Singh.cpp
 delete mode 100644 Week1/Xor operation/Anjali_Singh.cpp

diff --git a/Week1/Count Negative Nos/Anjali_Singh.cpp b/Week1/Count Negative Nos/Anjali_Singh.cpp
deleted file mode 100644
index a70ad65..0000000
--- a/Week1/Count Negative Nos/Anjali_Singh.cpp	
+++ /dev/null
@@ -1,15 +0,0 @@
-class Solution {
-public:
-    int countNegatives(vector<vector<int>>& grid) {
-        int r=grid.size(), c=grid[0].size();
-        int count=0;
-        for(int i=0; i<r; i++){
-            for(int j=0; j<c; j++){
-                if(grid[i][j]<0){
-                    count++;
-                }
-            }
-        }
-        return count;
-    }
-};
diff --git a/Week1/Count and Say/Anjali_Singh.cpp b/Week1/Count and Say/Anjali_Singh.cpp
deleted file mode 100644
index 5490a85..0000000
--- a/Week1/Count and Say/Anjali_Singh.cpp	
+++ /dev/null
@@ -1,18 +0,0 @@
-class Solution {
-public:
-    string countAndSay(int n) {
-        if(n==1)
-            return "1";
-
-        string res;
-        string pres = countAndSay(n-1);
-        int start = 0, i = 1;
-        for( ; i<pres.size(); i++ ){
-            if( pres[i]!=pres[i-1] ){
-                res += to_string(i-start) + pres[i-1];
-                start = i;
-            }
-        }
-        return res + to_string(i-start) + pres[i-1];
-    }
-};
diff --git a/Week1/Longest Substring wo repeating chars/Anjali_Singh.cpp b/Week1/Longest Substring wo repeating chars/Anjali_Singh.cpp
deleted file mode 100644
index 9c0afb4..0000000
--- a/Week1/Longest Substring wo repeating chars/Anjali_Singh.cpp	
+++ /dev/null
@@ -1,24 +0,0 @@
-class Solution {
-public:
-    int lengthOfLongestSubstring(string s) {
-        int res=0,n=s.size(),left=0;
-        unordered_map<char,int>mymap;
-        for(int i=0; i<n ;++i){
-            if(mymap.find(s[i])==mymap.end()){
-                mymap[s[i]]=i;
-            }
-            else{
-                if(mymap[s[i]]>=left){
-                    left=mymap[s[i]]+1;
-                    mymap[s[i]]=i;
-
-                }
-                else{
-                    mymap[s[i]]=i;
-                }
-            }
-            res=max(res,i-left+1);
-        }
-        return res;
-    }
-};
diff --git a/Week1/Max Subarray/Anjali_Singh.cpp b/Week1/Max Subarray/Anjali_Singh.cpp
deleted file mode 100644
index 12c679b..0000000
--- a/Week1/Max Subarray/Anjali_Singh.cpp	
+++ /dev/null
@@ -1,17 +0,0 @@
-class Solution {
-public:
-    int maxSubArray(vector<int>& nums) {
-        int sum=0, maxSum=INT_MIN;
-        for(int i=0; i<nums.size(); i++){
-            sum += nums[i];
-            if(sum>maxSum){
-                maxSum=sum;
-            }
-            if(sum<0){
-                sum=0;
-            }
-        }
-        return maxSum;
-
-        }
-};
diff --git a/Week1/Missing no/Anjali_Singh.cpp b/Week1/Missing no/Anjali_Singh.cpp
deleted file mode 100644
index 1431e5c..0000000
--- a/Week1/Missing no/Anjali_Singh.cpp	
+++ /dev/null
@@ -1,14 +0,0 @@
-class Solution {
-public:
-    int missingNumber(vector<int>& nums) {
-		sort(nums.begin(),nums.end());
-        cout<<nums.back();
-		if(nums[0]!=0) return 0;
-		for(int i=1;i<nums.size();i++){
-			if(nums[i]-nums[i-1]!=1){
-				return i;
-			}
-		}
-		return nums.back()+1;
-    }
-};
diff --git a/Week1/Monotonic Array/Anjali_Singh.cpp b/Week1/Monotonic Array/Anjali_Singh.cpp
deleted file mode 100644
index a03be7f..0000000
--- a/Week1/Monotonic Array/Anjali_Singh.cpp	
+++ /dev/null
@@ -1,20 +0,0 @@
-class Solution {
-public:
-    bool isMonotonic(vector<int>& A) {
-        int len = A.size();
-        int count1 = 1;
-        int count2 = 1;
-        for(int i = 1; i < len; i++){
-            if(A[i] >= A[i-1]){
-                count1++;
-                }
-            if(A[i] <= A[i-1]){
-                count2++;
-                }
-        }
-        if(count1 == len or count2 == len){
-            return true;
-    }
-        return false;
-    }
-};
diff --git a/Week1/Move Zeroes/Anjali_Singh.cpp b/Week1/Move Zeroes/Anjali_Singh.cpp
deleted file mode 100644
index 6440564..0000000
--- a/Week1/Move Zeroes/Anjali_Singh.cpp	
+++ /dev/null
@@ -1,12 +0,0 @@
-class Solution {
-public:
-    void moveZeroes(vector<int>& nums) {
-        for(int i=0, j=0; i<nums.size(); i++){
-                if(nums[i]!=0){
-                    cout<<nums[j]<<" "<<nums[i]<<endl;
-                    swap(nums[j++], nums[i]);
-
-            }
-        }
-    }
-};
diff --git a/Week1/Pascal Triangle/Anjali_Singh.cpp b/Week1/Pascal Triangle/Anjali_Singh.cpp
deleted file mode 100644
index 2a879ff..0000000
--- a/Week1/Pascal Triangle/Anjali_Singh.cpp	
+++ /dev/null
@@ -1,15 +0,0 @@
-class Solution {
-public:
-    vector<vector<int>> generate(int numRows) {
-        vector<vector<int>>ans;
-        for(int i=0;i<numRows;i++){
-            // make i+1 copies of 1 in row
-            vector<int>row(i+1,1);
-            for(int j=1;j<i;j++){
-                row[j] = ans[i-1][j] + ans[i-1][j-1];
-            }
-            ans.push_back(row);
-        }
-        return ans;
-    }
-};
diff --git a/Week1/Pivot Index/Anjali_Singh.cpp b/Week1/Pivot Index/Anjali_Singh.cpp
deleted file mode 100644
index e67caa2..0000000
--- a/Week1/Pivot Index/Anjali_Singh.cpp	
+++ /dev/null
@@ -1,28 +0,0 @@
-class Solution {
-public:
-    int pivotIndex(vector<int>& nums) {
-        int leftSum=0, rightSum=0, sum=0;
-        for(int i=0; i<nums.size(); i++){
-            sum += nums[i];
-
-        }
-        if(nums.size()!=0){
-        rightSum = sum - nums[0];
-        if(leftSum==rightSum){
-            return 0;
-        }
-        }
-        rightSum = 0;
-        for(int i=1; i<nums.size(); i++){
-            leftSum = leftSum + nums[i-1];
-            rightSum = sum -nums[i]-leftSum;
-            cout<<rightSum;
-            if(leftSum==rightSum){
-                return i;
-            }
-        }
-        return -1;
-
-
-    }
-};
diff --git a/Week1/Product Of Array/Anjali_Singh.cpp b/Week1/Product Of Array/Anjali_Singh.cpp
deleted file mode 100644
index ec50ab0..0000000
--- a/Week1/Product Of Array/Anjali_Singh.cpp	
+++ /dev/null
@@ -1,20 +0,0 @@
-class Solution {
-public:
-    vector<int> productExceptSelf(vector<int>& nums) {
-        vector<int> left(nums.size()), right(nums.size());
-        left[0] = 1;
-        right[nums.size()-1] = 1;
-        for(int i=1; i<nums.size(); i++){
-            left[i] = left[i-1]*nums[i-1];
-        }
-
-        for(int i=nums.size()-2; i>=0; i--){
-            right[i] = right[i+1]*nums[i+1];
-        }
-        for(int i=0; i<nums.size(); i++){
-            left[i] = left[i]*right[i];
-        }
-
-        return left;
-    }
-};
diff --git a/Week1/Remove Duplicates/Anjali_Singh.cpp b/Week1/Remove Duplicates/Anjali_Singh.cpp
deleted file mode 100644
index 146f2d4..0000000
--- a/Week1/Remove Duplicates/Anjali_Singh.cpp	
+++ /dev/null
@@ -1,20 +0,0 @@
-class Solution {
-public:
-    int removeDuplicates(vector<int>& nums) {
-        int n = nums.size();
-        if(n==0||n==1){
-            return n;
-        }
-    int temp[n];
-    int j = 0;
-    for (int i=0; i<n-1; i++)
-        if (nums[i] != nums[i+1])
-            temp[j++] = nums[i];
-    temp[j++] = nums[n-1];
-
-    for (int i=0; i<j; i++)
-        nums[i] = temp[i];
-    return j;
-
-    }
-};
diff --git a/Week1/Reverse Only Letters/Anjali_Singh.cpp b/Week1/Reverse Only Letters/Anjali_Singh.cpp
deleted file mode 100644
index 707ff50..0000000
--- a/Week1/Reverse Only Letters/Anjali_Singh.cpp	
+++ /dev/null
@@ -1,21 +0,0 @@
-class Solution {
-public:
-    string reverseOnlyLetters(string S) {
-        int l=0, r=S.size()-1;
-        while(l<r){
-            if(!isalpha(S[l])){
-                l++;
-            }
-            else if(!isalpha(S[r])){
-                r--;
-            }
-            else{
-                swap(S[l], S[r]);
-                l++;
-                r--;
-            }
-        }
-        return S;
-
-    }
-};
diff --git a/Week1/Reverse vowels/Anjali_Singh.cpp b/Week1/Reverse vowels/Anjali_Singh.cpp
deleted file mode 100644
index bd9af71..0000000
--- a/Week1/Reverse vowels/Anjali_Singh.cpp	
+++ /dev/null
@@ -1,29 +0,0 @@
-class Solution {
-public:
-    bool isVowel(char i){
-        i = tolower(i);
-        if(i=='a'||i=='e'||i=='i'||i=='u'||i=='o'){
-            return true;
-        }
-        return false;
-
-    }
-    string reverseVowels(string s) {
-        int l=0, r=s.size()-1;
-        while(l<r){
-            if(!isVowel(s[l])){
-                l++;
-            }
-            else if(!isVowel(s[r])){
-                r--;
-            }
-            else if(isVowel(s[l])&&isVowel(s[r])){
-                swap(s[l], s[r]);
-                l++;
-                r--;
-            }
-
-        }
-        return s;
-    }
-};
diff --git a/Week1/Rotate Array/Anjali_Singh.cpp b/Week1/Rotate Array/Anjali_Singh.cpp
deleted file mode 100644
index e90f0f1..0000000
--- a/Week1/Rotate Array/Anjali_Singh.cpp	
+++ /dev/null
@@ -1,22 +0,0 @@
-class Solution {
-public:
-    void rotate(vector<int>& nums, int k) {
-    //     while(k!=0){
-    //         int j = nums[nums.size()-1];
-    //     for(int i=nums.size()-1; i>0; i--){
-    //         nums[i] = nums[i-1];
-    //     }
-    //         nums[0] = j;
-    //         k--;
-    // }
-        int n=nums.size();
-        int a[n];
-        for(int i=0; i<n; i++){
-            a[(i+k)%n] = nums[i];
-        }
-        for(int i=0; i<n; i++){
-            nums[i] = a[i];
-        }
-
-    }
-};
diff --git a/Week1/Spiral Matrix/Anjali_Singh.cpp b/Week1/Spiral Matrix/Anjali_Singh.cpp
deleted file mode 100644
index f0a3064..0000000
--- a/Week1/Spiral Matrix/Anjali_Singh.cpp	
+++ /dev/null
@@ -1,33 +0,0 @@
-class Solution {
-public:
-    vector<int> spiralOrder(vector<vector<int>>& matrix) {
-        int r=matrix.size(), c=matrix[0].size();
-        vector<int> ans;
-        int k=0, l=0;
-        while(k<r && l<c){
-        for(int i=l; i<c; i++){
-            ans.push_back(matrix[k][i]);
-        }
-        k++;
-        for(int i=k; i<r; i++){
-            ans.push_back(matrix[i][c-1]);
-
-        }
-        c--;
-        if(k<r){
-        for(int i=c-1; i>=l; i--){
-            ans.push_back(matrix[r-1][i]);
-        }
-            r--;
-        }
-        if(l<c){
-        for(int i=r-1; i>=k; i--){
-            ans.push_back(matrix[i][l]);
-        }
-        l++;
-        }
-        }
-
-        return ans;
-    }
-};
diff --git a/Week1/Target Array/Anjali_Singh.cpp b/Week1/Target Array/Anjali_Singh.cpp
deleted file mode 100644
index 835ce56..0000000
--- a/Week1/Target Array/Anjali_Singh.cpp	
+++ /dev/null
@@ -1,13 +0,0 @@
-class Solution {
-public:
-    vector<int> createTargetArray(vector<int>& nums, vector<int>& index) {
-        vector<int>ans;
-        for(int i=0; i<nums.size();i++){
-            //insert() is a built-in function in C++ STL which inserts new elements before the element at the specified position, effectively increasing the container size by the number of elements inserted.
-            //To avoid overwriting in the array/vector
-            ans.insert(ans.begin()+index[i], nums[i]);
-        }
-        return ans;
-
-    }
-};
diff --git a/Week1/Valid Palindrome/Anjali_Singh.cpp b/Week1/Valid Palindrome/Anjali_Singh.cpp
deleted file mode 100644
index b8f9924..0000000
--- a/Week1/Valid Palindrome/Anjali_Singh.cpp	
+++ /dev/null
@@ -1,25 +0,0 @@
-class Solution {
-public:
-    bool isPalindrome(string s) {
-        transform(s.begin(), s.end(), s.begin(), ::tolower);
-        int l=0, r=s.size()-1;
-        while(l<r){
-            if((!isalpha(s[l]))&&(!isdigit(s[l]))){
-                l++;
-            }
-            else if((!isalpha(s[r]))&&(!isdigit(s[r]))){
-                r--;
-            }
-
-            else if(s[l]==s[r]){
-            l++;
-            r--;
-          }
-            else{
-                return false;
-            }
-    }
-
-        return true;
-    }
-};
diff --git a/Week1/Xor operation/Anjali_Singh.cpp b/Week1/Xor operation/Anjali_Singh.cpp
deleted file mode 100644
index b64720e..0000000
--- a/Week1/Xor operation/Anjali_Singh.cpp	
+++ /dev/null
@@ -1,15 +0,0 @@
-class Solution {
-public:
-    int xorOperation(int n, int start) {
-        vector<int> x;
-        int a=start, s;
-        for(int i=0; i<n; i++){
-            s = start + 2*i;
-            x.push_back(s);
-        }
-        for(int i=1; i<x.size(); i++){
-            a ^= x[i];
-        }
-        return a;
-    }
-};

From 816755812a16696b036fa8961455de168695a5e2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E2=80=9Cpikachu28?= <“anjalisinghgsm@“gmail.com>
Date: Mon, 7 Dec 2020 21:20:28 +0530
Subject: [PATCH 3/5] Week_1_Anjali_Singh

---
 Week1/Count Negative Nos/Anjali_Singh.cpp     | 15 +++++++++
 Week1/Count and Say/Anjali_Singh.cpp          | 18 ++++++++++
 .../Anjali_Singh.cpp                          | 24 ++++++++++++++
 Week1/Max Subarray/Anjali_Singh.cpp           | 17 ++++++++++
 Week1/Missing no/Anjali_Singh.cpp             | 14 ++++++++
 Week1/Monotonic Array/Anjali_Singh.cpp        |  0
 Week1/Move Zeroes/Anjali_Singh.cpp            | 12 +++++++
 Week1/Pascal Triangle/Anjali_Singh.cpp        | 15 +++++++++
 Week1/Pivot Index/Anjali_Singh.cpp            | 28 ++++++++++++++++
 Week1/Product Of Array/Anjali_Singh.cpp       | 20 +++++++++++
 Week1/Remove Duplicates/Anjali_Singh.cpp      | 20 +++++++++++
 Week1/Reverse Only Letters/Anjali_Singh.cpp   | 21 ++++++++++++
 Week1/Reverse vowels/Anjali_Singh.cpp         | 29 ++++++++++++++++
 Week1/Rotate Array/Anjali_Singh.cpp           | 22 +++++++++++++
 Week1/Spiral Matrix/Anjali_Singh.cpp          | 33 +++++++++++++++++++
 Week1/Target Array/Anjali_Singh.cpp           | 13 ++++++++
 Week1/Valid Palindrome/Anjali_Singh.cpp       | 25 ++++++++++++++
 Week1/Xor operation/Anjali_Singh.cpp          | 15 +++++++++
 18 files changed, 341 insertions(+)
 create mode 100644 Week1/Count Negative Nos/Anjali_Singh.cpp
 create mode 100644 Week1/Count and Say/Anjali_Singh.cpp
 create mode 100644 Week1/Longest Substring wo repeating chars/Anjali_Singh.cpp
 create mode 100644 Week1/Max Subarray/Anjali_Singh.cpp
 create mode 100644 Week1/Missing no/Anjali_Singh.cpp
 create mode 100644 Week1/Monotonic Array/Anjali_Singh.cpp
 create mode 100644 Week1/Move Zeroes/Anjali_Singh.cpp
 create mode 100644 Week1/Pascal Triangle/Anjali_Singh.cpp
 create mode 100644 Week1/Pivot Index/Anjali_Singh.cpp
 create mode 100644 Week1/Product Of Array/Anjali_Singh.cpp
 create mode 100644 Week1/Remove Duplicates/Anjali_Singh.cpp
 create mode 100644 Week1/Reverse Only Letters/Anjali_Singh.cpp
 create mode 100644 Week1/Reverse vowels/Anjali_Singh.cpp
 create mode 100644 Week1/Rotate Array/Anjali_Singh.cpp
 create mode 100644 Week1/Spiral Matrix/Anjali_Singh.cpp
 create mode 100644 Week1/Target Array/Anjali_Singh.cpp
 create mode 100644 Week1/Valid Palindrome/Anjali_Singh.cpp
 create mode 100644 Week1/Xor operation/Anjali_Singh.cpp

diff --git a/Week1/Count Negative Nos/Anjali_Singh.cpp b/Week1/Count Negative Nos/Anjali_Singh.cpp
new file mode 100644
index 0000000..a70ad65
--- /dev/null
+++ b/Week1/Count Negative Nos/Anjali_Singh.cpp	
@@ -0,0 +1,15 @@
+class Solution {
+public:
+    int countNegatives(vector<vector<int>>& grid) {
+        int r=grid.size(), c=grid[0].size();
+        int count=0;
+        for(int i=0; i<r; i++){
+            for(int j=0; j<c; j++){
+                if(grid[i][j]<0){
+                    count++;
+                }
+            }
+        }
+        return count;
+    }
+};
diff --git a/Week1/Count and Say/Anjali_Singh.cpp b/Week1/Count and Say/Anjali_Singh.cpp
new file mode 100644
index 0000000..5490a85
--- /dev/null
+++ b/Week1/Count and Say/Anjali_Singh.cpp	
@@ -0,0 +1,18 @@
+class Solution {
+public:
+    string countAndSay(int n) {
+        if(n==1)
+            return "1";
+
+        string res;
+        string pres = countAndSay(n-1);
+        int start = 0, i = 1;
+        for( ; i<pres.size(); i++ ){
+            if( pres[i]!=pres[i-1] ){
+                res += to_string(i-start) + pres[i-1];
+                start = i;
+            }
+        }
+        return res + to_string(i-start) + pres[i-1];
+    }
+};
diff --git a/Week1/Longest Substring wo repeating chars/Anjali_Singh.cpp b/Week1/Longest Substring wo repeating chars/Anjali_Singh.cpp
new file mode 100644
index 0000000..9c0afb4
--- /dev/null
+++ b/Week1/Longest Substring wo repeating chars/Anjali_Singh.cpp	
@@ -0,0 +1,24 @@
+class Solution {
+public:
+    int lengthOfLongestSubstring(string s) {
+        int res=0,n=s.size(),left=0;
+        unordered_map<char,int>mymap;
+        for(int i=0; i<n ;++i){
+            if(mymap.find(s[i])==mymap.end()){
+                mymap[s[i]]=i;
+            }
+            else{
+                if(mymap[s[i]]>=left){
+                    left=mymap[s[i]]+1;
+                    mymap[s[i]]=i;
+
+                }
+                else{
+                    mymap[s[i]]=i;
+                }
+            }
+            res=max(res,i-left+1);
+        }
+        return res;
+    }
+};
diff --git a/Week1/Max Subarray/Anjali_Singh.cpp b/Week1/Max Subarray/Anjali_Singh.cpp
new file mode 100644
index 0000000..12c679b
--- /dev/null
+++ b/Week1/Max Subarray/Anjali_Singh.cpp	
@@ -0,0 +1,17 @@
+class Solution {
+public:
+    int maxSubArray(vector<int>& nums) {
+        int sum=0, maxSum=INT_MIN;
+        for(int i=0; i<nums.size(); i++){
+            sum += nums[i];
+            if(sum>maxSum){
+                maxSum=sum;
+            }
+            if(sum<0){
+                sum=0;
+            }
+        }
+        return maxSum;
+
+        }
+};
diff --git a/Week1/Missing no/Anjali_Singh.cpp b/Week1/Missing no/Anjali_Singh.cpp
new file mode 100644
index 0000000..1431e5c
--- /dev/null
+++ b/Week1/Missing no/Anjali_Singh.cpp	
@@ -0,0 +1,14 @@
+class Solution {
+public:
+    int missingNumber(vector<int>& nums) {
+		sort(nums.begin(),nums.end());
+        cout<<nums.back();
+		if(nums[0]!=0) return 0;
+		for(int i=1;i<nums.size();i++){
+			if(nums[i]-nums[i-1]!=1){
+				return i;
+			}
+		}
+		return nums.back()+1;
+    }
+};
diff --git a/Week1/Monotonic Array/Anjali_Singh.cpp b/Week1/Monotonic Array/Anjali_Singh.cpp
new file mode 100644
index 0000000..e69de29
diff --git a/Week1/Move Zeroes/Anjali_Singh.cpp b/Week1/Move Zeroes/Anjali_Singh.cpp
new file mode 100644
index 0000000..6440564
--- /dev/null
+++ b/Week1/Move Zeroes/Anjali_Singh.cpp	
@@ -0,0 +1,12 @@
+class Solution {
+public:
+    void moveZeroes(vector<int>& nums) {
+        for(int i=0, j=0; i<nums.size(); i++){
+                if(nums[i]!=0){
+                    cout<<nums[j]<<" "<<nums[i]<<endl;
+                    swap(nums[j++], nums[i]);
+
+            }
+        }
+    }
+};
diff --git a/Week1/Pascal Triangle/Anjali_Singh.cpp b/Week1/Pascal Triangle/Anjali_Singh.cpp
new file mode 100644
index 0000000..2a879ff
--- /dev/null
+++ b/Week1/Pascal Triangle/Anjali_Singh.cpp	
@@ -0,0 +1,15 @@
+class Solution {
+public:
+    vector<vector<int>> generate(int numRows) {
+        vector<vector<int>>ans;
+        for(int i=0;i<numRows;i++){
+            // make i+1 copies of 1 in row
+            vector<int>row(i+1,1);
+            for(int j=1;j<i;j++){
+                row[j] = ans[i-1][j] + ans[i-1][j-1];
+            }
+            ans.push_back(row);
+        }
+        return ans;
+    }
+};
diff --git a/Week1/Pivot Index/Anjali_Singh.cpp b/Week1/Pivot Index/Anjali_Singh.cpp
new file mode 100644
index 0000000..e67caa2
--- /dev/null
+++ b/Week1/Pivot Index/Anjali_Singh.cpp	
@@ -0,0 +1,28 @@
+class Solution {
+public:
+    int pivotIndex(vector<int>& nums) {
+        int leftSum=0, rightSum=0, sum=0;
+        for(int i=0; i<nums.size(); i++){
+            sum += nums[i];
+
+        }
+        if(nums.size()!=0){
+        rightSum = sum - nums[0];
+        if(leftSum==rightSum){
+            return 0;
+        }
+        }
+        rightSum = 0;
+        for(int i=1; i<nums.size(); i++){
+            leftSum = leftSum + nums[i-1];
+            rightSum = sum -nums[i]-leftSum;
+            cout<<rightSum;
+            if(leftSum==rightSum){
+                return i;
+            }
+        }
+        return -1;
+
+
+    }
+};
diff --git a/Week1/Product Of Array/Anjali_Singh.cpp b/Week1/Product Of Array/Anjali_Singh.cpp
new file mode 100644
index 0000000..ec50ab0
--- /dev/null
+++ b/Week1/Product Of Array/Anjali_Singh.cpp	
@@ -0,0 +1,20 @@
+class Solution {
+public:
+    vector<int> productExceptSelf(vector<int>& nums) {
+        vector<int> left(nums.size()), right(nums.size());
+        left[0] = 1;
+        right[nums.size()-1] = 1;
+        for(int i=1; i<nums.size(); i++){
+            left[i] = left[i-1]*nums[i-1];
+        }
+
+        for(int i=nums.size()-2; i>=0; i--){
+            right[i] = right[i+1]*nums[i+1];
+        }
+        for(int i=0; i<nums.size(); i++){
+            left[i] = left[i]*right[i];
+        }
+
+        return left;
+    }
+};
diff --git a/Week1/Remove Duplicates/Anjali_Singh.cpp b/Week1/Remove Duplicates/Anjali_Singh.cpp
new file mode 100644
index 0000000..146f2d4
--- /dev/null
+++ b/Week1/Remove Duplicates/Anjali_Singh.cpp	
@@ -0,0 +1,20 @@
+class Solution {
+public:
+    int removeDuplicates(vector<int>& nums) {
+        int n = nums.size();
+        if(n==0||n==1){
+            return n;
+        }
+    int temp[n];
+    int j = 0;
+    for (int i=0; i<n-1; i++)
+        if (nums[i] != nums[i+1])
+            temp[j++] = nums[i];
+    temp[j++] = nums[n-1];
+
+    for (int i=0; i<j; i++)
+        nums[i] = temp[i];
+    return j;
+
+    }
+};
diff --git a/Week1/Reverse Only Letters/Anjali_Singh.cpp b/Week1/Reverse Only Letters/Anjali_Singh.cpp
new file mode 100644
index 0000000..707ff50
--- /dev/null
+++ b/Week1/Reverse Only Letters/Anjali_Singh.cpp	
@@ -0,0 +1,21 @@
+class Solution {
+public:
+    string reverseOnlyLetters(string S) {
+        int l=0, r=S.size()-1;
+        while(l<r){
+            if(!isalpha(S[l])){
+                l++;
+            }
+            else if(!isalpha(S[r])){
+                r--;
+            }
+            else{
+                swap(S[l], S[r]);
+                l++;
+                r--;
+            }
+        }
+        return S;
+
+    }
+};
diff --git a/Week1/Reverse vowels/Anjali_Singh.cpp b/Week1/Reverse vowels/Anjali_Singh.cpp
new file mode 100644
index 0000000..bd9af71
--- /dev/null
+++ b/Week1/Reverse vowels/Anjali_Singh.cpp	
@@ -0,0 +1,29 @@
+class Solution {
+public:
+    bool isVowel(char i){
+        i = tolower(i);
+        if(i=='a'||i=='e'||i=='i'||i=='u'||i=='o'){
+            return true;
+        }
+        return false;
+
+    }
+    string reverseVowels(string s) {
+        int l=0, r=s.size()-1;
+        while(l<r){
+            if(!isVowel(s[l])){
+                l++;
+            }
+            else if(!isVowel(s[r])){
+                r--;
+            }
+            else if(isVowel(s[l])&&isVowel(s[r])){
+                swap(s[l], s[r]);
+                l++;
+                r--;
+            }
+
+        }
+        return s;
+    }
+};
diff --git a/Week1/Rotate Array/Anjali_Singh.cpp b/Week1/Rotate Array/Anjali_Singh.cpp
new file mode 100644
index 0000000..e90f0f1
--- /dev/null
+++ b/Week1/Rotate Array/Anjali_Singh.cpp	
@@ -0,0 +1,22 @@
+class Solution {
+public:
+    void rotate(vector<int>& nums, int k) {
+    //     while(k!=0){
+    //         int j = nums[nums.size()-1];
+    //     for(int i=nums.size()-1; i>0; i--){
+    //         nums[i] = nums[i-1];
+    //     }
+    //         nums[0] = j;
+    //         k--;
+    // }
+        int n=nums.size();
+        int a[n];
+        for(int i=0; i<n; i++){
+            a[(i+k)%n] = nums[i];
+        }
+        for(int i=0; i<n; i++){
+            nums[i] = a[i];
+        }
+
+    }
+};
diff --git a/Week1/Spiral Matrix/Anjali_Singh.cpp b/Week1/Spiral Matrix/Anjali_Singh.cpp
new file mode 100644
index 0000000..f0a3064
--- /dev/null
+++ b/Week1/Spiral Matrix/Anjali_Singh.cpp	
@@ -0,0 +1,33 @@
+class Solution {
+public:
+    vector<int> spiralOrder(vector<vector<int>>& matrix) {
+        int r=matrix.size(), c=matrix[0].size();
+        vector<int> ans;
+        int k=0, l=0;
+        while(k<r && l<c){
+        for(int i=l; i<c; i++){
+            ans.push_back(matrix[k][i]);
+        }
+        k++;
+        for(int i=k; i<r; i++){
+            ans.push_back(matrix[i][c-1]);
+
+        }
+        c--;
+        if(k<r){
+        for(int i=c-1; i>=l; i--){
+            ans.push_back(matrix[r-1][i]);
+        }
+            r--;
+        }
+        if(l<c){
+        for(int i=r-1; i>=k; i--){
+            ans.push_back(matrix[i][l]);
+        }
+        l++;
+        }
+        }
+
+        return ans;
+    }
+};
diff --git a/Week1/Target Array/Anjali_Singh.cpp b/Week1/Target Array/Anjali_Singh.cpp
new file mode 100644
index 0000000..835ce56
--- /dev/null
+++ b/Week1/Target Array/Anjali_Singh.cpp	
@@ -0,0 +1,13 @@
+class Solution {
+public:
+    vector<int> createTargetArray(vector<int>& nums, vector<int>& index) {
+        vector<int>ans;
+        for(int i=0; i<nums.size();i++){
+            //insert() is a built-in function in C++ STL which inserts new elements before the element at the specified position, effectively increasing the container size by the number of elements inserted.
+            //To avoid overwriting in the array/vector
+            ans.insert(ans.begin()+index[i], nums[i]);
+        }
+        return ans;
+
+    }
+};
diff --git a/Week1/Valid Palindrome/Anjali_Singh.cpp b/Week1/Valid Palindrome/Anjali_Singh.cpp
new file mode 100644
index 0000000..b8f9924
--- /dev/null
+++ b/Week1/Valid Palindrome/Anjali_Singh.cpp	
@@ -0,0 +1,25 @@
+class Solution {
+public:
+    bool isPalindrome(string s) {
+        transform(s.begin(), s.end(), s.begin(), ::tolower);
+        int l=0, r=s.size()-1;
+        while(l<r){
+            if((!isalpha(s[l]))&&(!isdigit(s[l]))){
+                l++;
+            }
+            else if((!isalpha(s[r]))&&(!isdigit(s[r]))){
+                r--;
+            }
+
+            else if(s[l]==s[r]){
+            l++;
+            r--;
+          }
+            else{
+                return false;
+            }
+    }
+
+        return true;
+    }
+};
diff --git a/Week1/Xor operation/Anjali_Singh.cpp b/Week1/Xor operation/Anjali_Singh.cpp
new file mode 100644
index 0000000..b64720e
--- /dev/null
+++ b/Week1/Xor operation/Anjali_Singh.cpp	
@@ -0,0 +1,15 @@
+class Solution {
+public:
+    int xorOperation(int n, int start) {
+        vector<int> x;
+        int a=start, s;
+        for(int i=0; i<n; i++){
+            s = start + 2*i;
+            x.push_back(s);
+        }
+        for(int i=1; i<x.size(); i++){
+            a ^= x[i];
+        }
+        return a;
+    }
+};

From e32c07d8bad7c0af148bf0ba28515e23b12f3824 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E2=80=9Cpikachu28?= <“anjalisinghgsm@“gmail.com>
Date: Mon, 7 Dec 2020 21:22:08 +0530
Subject: [PATCH 4/5] Update Anjali_Singh.cpp

---
 Week1/Monotonic Array/Anjali_Singh.cpp | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/Week1/Monotonic Array/Anjali_Singh.cpp b/Week1/Monotonic Array/Anjali_Singh.cpp
index e69de29..a03be7f 100644
--- a/Week1/Monotonic Array/Anjali_Singh.cpp	
+++ b/Week1/Monotonic Array/Anjali_Singh.cpp	
@@ -0,0 +1,20 @@
+class Solution {
+public:
+    bool isMonotonic(vector<int>& A) {
+        int len = A.size();
+        int count1 = 1;
+        int count2 = 1;
+        for(int i = 1; i < len; i++){
+            if(A[i] >= A[i-1]){
+                count1++;
+                }
+            if(A[i] <= A[i-1]){
+                count2++;
+                }
+        }
+        if(count1 == len or count2 == len){
+            return true;
+    }
+        return false;
+    }
+};

From a5112e9a6dd5a49475504d6368aca6c0962ba31e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E2=80=9Cpikachu28?= <“anjalisinghgsm@“gmail.com>
Date: Fri, 15 Jan 2021 15:00:11 +0530
Subject: [PATCH 5/5] Week_2_Anjali_Singh

---
 Miscellaneous/Binary_Search/Anjali_Singh.cpp  | 16 +++++
 .../Duplicate_Number/Anjali_Singh.cpp         | 12 ++++
 Miscellaneous/Peek_Index/Anjali_Singh.cpp     | 16 +++++
 .../BackSpace_String_Compare/Anjali_Singh.cpp | 50 ++++++++++++++++
 Stacks/Make_string_great/Anjali_Singh.cpp     | 21 +++++++
 Stacks/Next_Greater_Element/Anjali_Singh.cpp  | 24 ++++++++
 .../Anjali_SIngh.cpp                          | 24 ++++++++
 .../Anjali_Singh.cpp                          | 49 +++++++++++++++
 .../Reverse_Polish_Notation/Anjali_Singh.cpp  | 32 ++++++++++
 Stacks/Valid_Parentheses/Anjali_Singh.cpp     | 20 +++++++
 .../Anjali_Singh.cpp                          | 46 +++++++++++++++
 Week2/Intersection_of_2_LL/Anjali_Singh.cpp   | 59 +++++++++++++++++++
 Week2/Linked_List_Cycle/Anjali_Singh.cpp      | 33 +++++++++++
 Week2/Merge_2_Sorted_List/Anjali_Singh.cpp    | 27 +++++++++
 .../Middle_of_the_LinkedList/Anjali_Singh.cpp | 22 +++++++
 Week2/Odd_Even_LL/Anjali_Singh.cpp            | 43 ++++++++++++++
 Week2/Palindrome_LinkedList/Anjali_Singh.cpp  | 42 +++++++++++++
 .../Anjali_Singh.cpp                          | 25 ++++++++
 Week2/Remove_Nth_end_of_List/Anjali_Singh.cpp | 36 +++++++++++
 Week2/Reverse_Linked_List/Anjali_Singh.cpp    | 24 ++++++++
 Week2/Sort_List/Anjali_Singh.cpp              | 46 +++++++++++++++
 21 files changed, 667 insertions(+)
 create mode 100644 Miscellaneous/Binary_Search/Anjali_Singh.cpp
 create mode 100644 Miscellaneous/Duplicate_Number/Anjali_Singh.cpp
 create mode 100644 Miscellaneous/Peek_Index/Anjali_Singh.cpp
 create mode 100644 Stacks/BackSpace_String_Compare/Anjali_Singh.cpp
 create mode 100644 Stacks/Make_string_great/Anjali_Singh.cpp
 create mode 100644 Stacks/Next_Greater_Element/Anjali_Singh.cpp
 create mode 100644 Stacks/Remove_Adjacent_Duplicates_In_String/Anjali_SIngh.cpp
 create mode 100644 Stacks/Remove_Outermost_Parentheses/Anjali_Singh.cpp
 create mode 100644 Stacks/Reverse_Polish_Notation/Anjali_Singh.cpp
 create mode 100644 Stacks/Valid_Parentheses/Anjali_Singh.cpp
 create mode 100644 Week2/Convert_Binary_Number_LinkedList_to_Integer/Anjali_Singh.cpp
 create mode 100644 Week2/Intersection_of_2_LL/Anjali_Singh.cpp
 create mode 100644 Week2/Linked_List_Cycle/Anjali_Singh.cpp
 create mode 100644 Week2/Merge_2_Sorted_List/Anjali_Singh.cpp
 create mode 100644 Week2/Middle_of_the_LinkedList/Anjali_Singh.cpp
 create mode 100644 Week2/Odd_Even_LL/Anjali_Singh.cpp
 create mode 100644 Week2/Palindrome_LinkedList/Anjali_Singh.cpp
 create mode 100644 Week2/Remove_Duplicate_from_Sorted_List/Anjali_Singh.cpp
 create mode 100644 Week2/Remove_Nth_end_of_List/Anjali_Singh.cpp
 create mode 100644 Week2/Reverse_Linked_List/Anjali_Singh.cpp
 create mode 100644 Week2/Sort_List/Anjali_Singh.cpp

diff --git a/Miscellaneous/Binary_Search/Anjali_Singh.cpp b/Miscellaneous/Binary_Search/Anjali_Singh.cpp
new file mode 100644
index 0000000..860743e
--- /dev/null
+++ b/Miscellaneous/Binary_Search/Anjali_Singh.cpp
@@ -0,0 +1,16 @@
+class Solution {
+public:
+    int BinarySearch(vector<int>nums, int l, int r, int target){
+        if(r>=l){
+            int mid = l + (r-l)/2;
+            if(nums[mid]==target) return mid;
+            else if(nums[mid]>target) return BinarySearch(nums, l, mid-1, target);
+            else return BinarySearch(nums, mid+1, r, target);
+        }
+        return -1;
+    }
+    int search(vector<int>& nums, int target) {
+        int x = BinarySearch(nums, 0, nums.size()-1, target);
+        return x;
+    }
+};
diff --git a/Miscellaneous/Duplicate_Number/Anjali_Singh.cpp b/Miscellaneous/Duplicate_Number/Anjali_Singh.cpp
new file mode 100644
index 0000000..f5609dd
--- /dev/null
+++ b/Miscellaneous/Duplicate_Number/Anjali_Singh.cpp
@@ -0,0 +1,12 @@
+class Solution {
+public:
+    int findDuplicate(vector<int>& nums) {
+        sort(nums.begin(), nums.end());
+        for(int i=0; i<nums.size(); i++){
+                if(nums[i]==nums[i+1])
+                    return nums[i];
+
+        }
+        return NULL;
+    }
+};
diff --git a/Miscellaneous/Peek_Index/Anjali_Singh.cpp b/Miscellaneous/Peek_Index/Anjali_Singh.cpp
new file mode 100644
index 0000000..860743e
--- /dev/null
+++ b/Miscellaneous/Peek_Index/Anjali_Singh.cpp
@@ -0,0 +1,16 @@
+class Solution {
+public:
+    int BinarySearch(vector<int>nums, int l, int r, int target){
+        if(r>=l){
+            int mid = l + (r-l)/2;
+            if(nums[mid]==target) return mid;
+            else if(nums[mid]>target) return BinarySearch(nums, l, mid-1, target);
+            else return BinarySearch(nums, mid+1, r, target);
+        }
+        return -1;
+    }
+    int search(vector<int>& nums, int target) {
+        int x = BinarySearch(nums, 0, nums.size()-1, target);
+        return x;
+    }
+};
diff --git a/Stacks/BackSpace_String_Compare/Anjali_Singh.cpp b/Stacks/BackSpace_String_Compare/Anjali_Singh.cpp
new file mode 100644
index 0000000..980c425
--- /dev/null
+++ b/Stacks/BackSpace_String_Compare/Anjali_Singh.cpp
@@ -0,0 +1,50 @@
+class Solution {
+public:
+     bool isEqual(stack<char> &stack1, stack<char> &stack2) {
+    if (stack1.empty() && stack2.empty())
+      return true;
+    else if (stack1.empty() || stack2.empty())
+      return false;
+    while (!stack1.empty() && !stack2.empty())
+    {
+      if (stack1.top() != stack2.top())
+        return false;
+      stack1.pop();
+      stack2.pop();
+    }
+    if (stack1.empty() && stack2.empty())
+      return true;
+    else
+      return false;
+  }
+
+    bool backspaceCompare(string S, string T) {
+        stack<char> stack1;
+        stack<char> stack2;
+        for(char s:S){
+            if(s=='#' && !stack1.empty()){
+                // cout<<s<<" ";
+                // cout<<stack1.top();
+                stack1.pop();
+                //cout<<stack1.top();
+            }
+            else if(s!='#'){
+                //cout<<s<<endl;
+                stack1.push(s);
+            }
+        }
+        for(char t:T){
+            if(t=='#' && !stack2.empty()){
+                stack2.pop();
+            }
+            else if(t!='#'){
+                //cout<<t<<" ";
+                stack2.push(t);
+            }
+        }
+       cout<<stack1.size()<<" "<<stack2.size()<<endl;
+       // cout<<isEqual(stack1, stack2);
+        return isEqual(stack1, stack2);
+
+    }
+};
diff --git a/Stacks/Make_string_great/Anjali_Singh.cpp b/Stacks/Make_string_great/Anjali_Singh.cpp
new file mode 100644
index 0000000..22f85df
--- /dev/null
+++ b/Stacks/Make_string_great/Anjali_Singh.cpp
@@ -0,0 +1,21 @@
+class Solution {
+public:
+        string makeGood(string s) {
+        stack<char> stk;
+        string ans;
+        for(char i: s){
+            if(!stk.empty() && (i==stk.top()-32||i==stk.top()+32)){
+                cout<<stk.top()+32;
+                cout<<i<<" "<<stk.top();
+                stk.pop();
+                ans.pop_back();
+            }
+            else{
+                stk.push(i);
+                ans.push_back(i);
+            }
+        }
+        return ans;
+    }
+
+};
diff --git a/Stacks/Next_Greater_Element/Anjali_Singh.cpp b/Stacks/Next_Greater_Element/Anjali_Singh.cpp
new file mode 100644
index 0000000..e3280c4
--- /dev/null
+++ b/Stacks/Next_Greater_Element/Anjali_Singh.cpp
@@ -0,0 +1,24 @@
+class Solution {
+public:
+    vector<int> nextGreaterElement(vector<int>& nums1, vector<int>& nums2) {
+
+	stack<int> st;
+	unordered_map<int,int> hashmap;
+	for(int i=nums2.size()-1;i>=0;i--)
+	{
+		while(!st.empty()&&st.top()<nums2[i])
+			st.pop();
+		if(st.empty())
+			hashmap[nums2[i]]=-1;
+		else
+			hashmap[nums2[i]]=st.top();
+		st.push(nums2[i]);
+	}
+	for(int i=0;i<nums1.size();i++)
+	{
+		nums1[i]=hashmap[nums1[i]];
+	}
+	return nums1;
+
+    }
+};
diff --git a/Stacks/Remove_Adjacent_Duplicates_In_String/Anjali_SIngh.cpp b/Stacks/Remove_Adjacent_Duplicates_In_String/Anjali_SIngh.cpp
new file mode 100644
index 0000000..db1f156
--- /dev/null
+++ b/Stacks/Remove_Adjacent_Duplicates_In_String/Anjali_SIngh.cpp
@@ -0,0 +1,24 @@
+class Solution {
+public:
+    string removeDuplicates(string S) {
+        stack<char> stk;
+        string ans;
+        for(char s: S){
+            if(!stk.empty() && s==stk.top())
+            {
+                stk.pop();
+            }
+            else{
+                stk.push(s);
+            }
+        }
+        while(!stk.empty()){
+            ans.push_back(stk.top());
+            cout<<stk.top()<<" ";
+            stk.pop();
+        }
+        reverse(ans.begin(), ans.end());
+        return ans;
+
+    }
+};
diff --git a/Stacks/Remove_Outermost_Parentheses/Anjali_Singh.cpp b/Stacks/Remove_Outermost_Parentheses/Anjali_Singh.cpp
new file mode 100644
index 0000000..64788b9
--- /dev/null
+++ b/Stacks/Remove_Outermost_Parentheses/Anjali_Singh.cpp
@@ -0,0 +1,49 @@
+class Solution {
+public:
+    string removeOuterParentheses(string S) {
+
+        stack <char> st;
+        string ans;
+
+
+
+        for(char& c : S)
+        {
+            //for opening brackets
+            // if it is not the outer most bracket then we will take it into ans string and push it to stack for later comparison.
+            if (c == '(' && st.size()>=1)
+            {
+                ans.push_back('(');
+                st.push('(');
+            }
+            // if c is outer most bracket then push it into stack for later comparison
+            else
+            {
+                if (c == '(' && st.size() == 0)
+                {
+                    st.push('(');
+                }
+            }
+
+
+            //for closing brackets
+
+            if (c == ')' && st.size()>1)
+            {
+                ans.push_back(')');
+                st.pop();
+            }
+            else
+            {
+                if (c == ')' && st.size() == 1)
+                {
+                    st.pop();
+                }
+            }
+        }
+
+
+        return ans;
+
+    }
+};
diff --git a/Stacks/Reverse_Polish_Notation/Anjali_Singh.cpp b/Stacks/Reverse_Polish_Notation/Anjali_Singh.cpp
new file mode 100644
index 0000000..f64a75b
--- /dev/null
+++ b/Stacks/Reverse_Polish_Notation/Anjali_Singh.cpp
@@ -0,0 +1,32 @@
+class Solution {
+public:
+    int evalRPN(vector<string>& tokens) {
+        unordered_set<string> operands = {"+", "-", "*", "/"};
+        stack<int> s;
+        for (string token : tokens) {
+            // We have a number
+            if (operands.find(token) == operands.end()) {
+                s.push(stoi(token));
+            }
+            else { // We have an operand
+                int b = s.top();
+                s.pop();
+                int a = s.top();
+                s.pop();
+                if (token == "+") {
+                    s.push(a + b);
+                }
+                else if (token == "-") {
+                    s.push(a - b);
+                }
+                else if (token == "*") {
+                    s.push(a * b);
+                }
+                else if (token == "/") {
+                    s.push(a / b);
+                }
+            }
+        }
+        return s.top();
+    }
+};
diff --git a/Stacks/Valid_Parentheses/Anjali_Singh.cpp b/Stacks/Valid_Parentheses/Anjali_Singh.cpp
new file mode 100644
index 0000000..68f80ee
--- /dev/null
+++ b/Stacks/Valid_Parentheses/Anjali_Singh.cpp
@@ -0,0 +1,20 @@
+class Solution {
+public:
+    bool isValid(string s) {
+    stack<char> stk;
+    for (char c : s) {
+        if (c == '(' || c == '{' || c == '[') {
+            stk.push(c);
+            continue;
+        }
+        // now we've all closing brackets
+        if (stk.empty()) return false;
+
+        if (c == ')' && stk.top() != '(') return false;
+        if (c == '}' && stk.top() != '{') return false;
+        if (c == ']' && stk.top() != '[') return false;
+        stk.pop();
+    }
+    return stk.empty();
+    }
+};
diff --git a/Week2/Convert_Binary_Number_LinkedList_to_Integer/Anjali_Singh.cpp b/Week2/Convert_Binary_Number_LinkedList_to_Integer/Anjali_Singh.cpp
new file mode 100644
index 0000000..a435a55
--- /dev/null
+++ b/Week2/Convert_Binary_Number_LinkedList_to_Integer/Anjali_Singh.cpp
@@ -0,0 +1,46 @@
+/**
+ * Definition for singly-linked list.
+ * struct ListNode {
+ *     int val;
+ *     ListNode *next;
+ *     ListNode() : val(0), next(nullptr) {}
+ *     ListNode(int x) : val(x), next(nullptr) {}
+ *     ListNode(int x, ListNode *next) : val(x), next(next) {}
+ * };
+ */
+class Solution {
+public:
+    ListNode* MergeList(ListNode* hd1, ListNode* hd2){
+        if (hd1==NULL && hd2==NULL) return NULL;
+        if (hd1==NULL) return hd2;
+        if (hd2==NULL) return hd1;
+        if (hd1->val<hd2->val){
+            ///Node* nh=hd1;
+            hd1->next=MergeList(hd1->next,hd2);
+            return hd1;
+        } else {
+            hd2->next=MergeList(hd1,hd2->next);
+            return hd2;
+        }
+    }
+
+    ListNode* MidSplit(ListNode* hd){
+        if (hd==NULL||hd->next==NULL) return hd;
+        ListNode* fp=hd, *sp=hd;
+        while (fp->next!=NULL&&fp->next->next!=NULL){
+            sp=sp->next;
+            fp=fp->next->next;
+        }
+        ListNode* nh=sp->next;
+        sp->next=NULL;
+        return nh;
+    }
+    ListNode* sortList(ListNode* head) {
+        if (head==NULL||head->next==NULL) return head;
+        ListNode* nh=MidSplit(head);
+        head=sortList(head);
+        nh=sortList(nh);
+        return MergeList(head, nh);
+
+    }
+};
diff --git a/Week2/Intersection_of_2_LL/Anjali_Singh.cpp b/Week2/Intersection_of_2_LL/Anjali_Singh.cpp
new file mode 100644
index 0000000..0fc5934
--- /dev/null
+++ b/Week2/Intersection_of_2_LL/Anjali_Singh.cpp
@@ -0,0 +1,59 @@
+/**
+ * Definition for singly-linked list.
+ * struct ListNode {
+ *     int val;
+ *     ListNode *next;
+ *     ListNode(int x) : val(x), next(NULL) {}
+ * };
+ */
+class Solution {
+public:
+    ListNode *getIntersectionNode(ListNode *headA, ListNode *headB) {
+        if(headA==NULL||headB==NULL)
+            return NULL;
+        if(headB==headA)
+            return headA;
+        ListNode *tailA = headA;
+        ListNode *tailB = headB;
+        ListNode *tailsA = headA;
+        ListNode *tailsB = headB;
+        ListNode *x = NULL;
+        int sizeA=0, sizeB=0;
+        for(int i = 0; tailsA!=NULL; i++)
+        {
+            sizeA = i;
+            tailsA = tailsA->next;
+        }
+        for(int i = 0; tailsB!=NULL; i++)
+        {
+            sizeB = i;
+            tailsB = tailsB->next;
+        }
+
+        sizeA++;
+        sizeB++;
+        while(tailA!=NULL&&tailB!=NULL)
+        {
+            if(sizeA>sizeB){
+                x = tailA;
+                while(x!=NULL){
+                if(tailB==x)
+                    return x;
+                x = x->next;
+            }
+            }
+            else{
+                x = tailB;
+            while(x!=NULL){
+                if(tailA==x)
+                    return x;
+                x = x->next;
+            }
+        }
+            tailB = tailB->next;
+            tailA = tailA->next;
+
+        }
+        return NULL;
+    }
+};
diff --git a/Week2/Linked_List_Cycle/Anjali_Singh.cpp b/Week2/Linked_List_Cycle/Anjali_Singh.cpp
new file mode 100644
index 0000000..7e19674
--- /dev/null
+++ b/Week2/Linked_List_Cycle/Anjali_Singh.cpp
@@ -0,0 +1,33 @@
+/**
+ * Definition for singly-linked list.
+ * struct ListNode {
+ *     int val;
+ *     ListNode *next;
+ *     ListNode(int x) : val(x), next(NULL) {}
+ * };
+ */
+class Solution {
+public:
+    bool hasCycle(ListNode *head) {
+        ListNode* sp=head,*fp=head;
+        if(head==NULL || head->next==NULL){
+            return false;
+        }
+        while (true){
+            if (fp==NULL || fp->next==NULL){
+                return false;
+            }
+            sp=sp->next;
+            fp=fp->next->next;
+            if (sp==fp) break;
+        }
+        // sp=head;
+        // while (true){
+        //     sp=sp->next;
+        //     fp=fp->next;
+        //     if (sp==fp) break;
+        // }
+        return true;
+
+    }
+};
diff --git a/Week2/Merge_2_Sorted_List/Anjali_Singh.cpp b/Week2/Merge_2_Sorted_List/Anjali_Singh.cpp
new file mode 100644
index 0000000..aaa9030
--- /dev/null
+++ b/Week2/Merge_2_Sorted_List/Anjali_Singh.cpp
@@ -0,0 +1,27 @@
+/**
+ * Definition for singly-linked list.
+ * struct ListNode {
+ *     int val;
+ *     ListNode *next;
+ *     ListNode() : val(0), next(nullptr) {}
+ *     ListNode(int x) : val(x), next(nullptr) {}
+ *     ListNode(int x, ListNode *next) : val(x), next(next) {}
+ * };
+ */
+class Solution {
+public:
+
+    ListNode* mergeTwoLists(ListNode* l1, ListNode* l2) {
+        if (l1==NULL && l2==NULL) return NULL;
+        if (l1==NULL) return l2;
+        if (l2==NULL) return l1;
+        if (l1->val<l2->val){
+            ///Node* nh=hd1;
+            l1->next=mergeTwoLists(l1->next,l2);
+            return l1;
+        } else {
+            l2->next=mergeTwoLists(l1,l2->next);
+            return l2;
+        }
+    }
+};
diff --git a/Week2/Middle_of_the_LinkedList/Anjali_Singh.cpp b/Week2/Middle_of_the_LinkedList/Anjali_Singh.cpp
new file mode 100644
index 0000000..fab2ba8
--- /dev/null
+++ b/Week2/Middle_of_the_LinkedList/Anjali_Singh.cpp
@@ -0,0 +1,22 @@
+/**
+ * Definition for singly-linked list.
+ * struct ListNode {
+ *     int val;
+ *     ListNode *next;
+ *     ListNode() : val(0), next(nullptr) {}
+ *     ListNode(int x) : val(x), next(nullptr) {}
+ *     ListNode(int x, ListNode *next) : val(x), next(next) {}
+ * };
+ */
+class Solution {
+public:
+    ListNode* middleNode(ListNode* head) {
+        ListNode *fp = head;
+        ListNode *sp = head;
+        while(fp!=NULL && fp->next!=NULL){
+            sp = sp->next;
+            fp= fp->next->next;
+        }
+        return sp;
+    }
+};
diff --git a/Week2/Odd_Even_LL/Anjali_Singh.cpp b/Week2/Odd_Even_LL/Anjali_Singh.cpp
new file mode 100644
index 0000000..9bdec07
--- /dev/null
+++ b/Week2/Odd_Even_LL/Anjali_Singh.cpp
@@ -0,0 +1,43 @@
+/**
+ * Definition for singly-linked list.
+ * struct ListNode {
+ *     int val;
+ *     ListNode *next;
+ *     ListNode() : val(0), next(nullptr) {}
+ *     ListNode(int x) : val(x), next(nullptr) {}
+ *     ListNode(int x, ListNode *next) : val(x), next(next) {}
+ * };
+ */
+class Solution {
+public:
+    ListNode* oddEvenList(ListNode* head) {
+        if(head==NULL)
+            return NULL;
+        ListNode* odd = head;
+        ListNode* even = head->next;
+        ListNode *evenFirst = even;
+
+        while(true){
+            if (!odd || !even || !(even->next))
+        {
+            odd->next = evenFirst;
+            break;
+        }
+             odd->next = even->next; //even's next position will be obivously odd and thus will be become next position
+            odd = even->next;  // moving odd pointer to next odd position
+            if(odd->next==NULL){
+                even->next = NULL;
+                odd->next = evenFirst; // connecting odd and even LL together
+                break;
+
+            }
+            even->next = odd->next;
+            even = odd->next;
+
+        }
+
+    return head;
+    }
+
+
+};
diff --git a/Week2/Palindrome_LinkedList/Anjali_Singh.cpp b/Week2/Palindrome_LinkedList/Anjali_Singh.cpp
new file mode 100644
index 0000000..a9537b3
--- /dev/null
+++ b/Week2/Palindrome_LinkedList/Anjali_Singh.cpp
@@ -0,0 +1,42 @@
+/**
+ * Definition for singly-linked list.
+ * struct ListNode {
+ *     int val;
+ *     ListNode *next;
+ *     ListNode() : val(0), next(nullptr) {}
+ *     ListNode(int x) : val(x), next(nullptr) {}
+ *     ListNode(int x, ListNode *next) : val(x), next(next) {}
+ * };
+ */
+class Solution {
+public:
+
+    bool isPalindrome(ListNode* head) {
+        if(head==NULL || head->next==NULL) return true;
+        ListNode *temp = reverseList(head);
+        ListNode *tempA = head;
+        while(tempA!=NULL && temp!=NULL){
+            if(temp->val != tempA->val){
+                return false;
+            }
+            cout<<temp->next->val<<" ";
+            cout<<tempA->next->val<<" ";
+            temp = temp->next;
+            tempA = tempA->next;
+        }
+        return true;
+    }
+
+        ListNode* reverseList(ListNode* head) {
+        if(head==NULL)
+            return NULL;
+        if(head->next==NULL)
+            return head;
+        ListNode *ans = reverseList(head->next);
+        head->next->next=head;
+        head->next=NULL;
+        return ans;
+
+    }
+
+};
diff --git a/Week2/Remove_Duplicate_from_Sorted_List/Anjali_Singh.cpp b/Week2/Remove_Duplicate_from_Sorted_List/Anjali_Singh.cpp
new file mode 100644
index 0000000..c7c92f4
--- /dev/null
+++ b/Week2/Remove_Duplicate_from_Sorted_List/Anjali_Singh.cpp
@@ -0,0 +1,25 @@
+/**
+ * Definition for singly-linked list.
+ * struct ListNode {
+ *     int val;
+ *     ListNode *next;
+ *     ListNode() : val(0), next(nullptr) {}
+ *     ListNode(int x) : val(x), next(nullptr) {}
+ *     ListNode(int x, ListNode *next) : val(x), next(next) {}
+ * };
+ */
+class Solution {
+public:
+    ListNode* deleteDuplicates(ListNode* head) {
+        ListNode* temp=head;
+        while(temp!=NULL&&temp->next!=NULL){
+            if(temp->val == temp->next->val){
+                temp->next = temp->next->next;
+            }
+            else{
+            temp = temp->next;
+            }
+        }
+        return head;
+    }
+};
diff --git a/Week2/Remove_Nth_end_of_List/Anjali_Singh.cpp b/Week2/Remove_Nth_end_of_List/Anjali_Singh.cpp
new file mode 100644
index 0000000..8830995
--- /dev/null
+++ b/Week2/Remove_Nth_end_of_List/Anjali_Singh.cpp
@@ -0,0 +1,36 @@
+/**
+ * Definition for singly-linked list.
+ * struct ListNode {
+ *     int val;
+ *     ListNode *next;
+ *     ListNode() : val(0), next(nullptr) {}
+ *     ListNode(int x) : val(x), next(nullptr) {}
+ *     ListNode(int x, ListNode *next) : val(x), next(next) {}
+ * };
+ */
+class Solution {
+public:
+    ListNode* removeNthFromEnd(ListNode* head, int n) {
+        ListNode* first = head;
+        ListNode* second = head;
+        while(second->next!=NULL){
+            if(n>0){
+                second = second->next;
+                n--;
+            }
+            else{
+                first = first->next;
+                second = second->next;
+            }
+        }
+        if(n==0){
+            first->next = first->next->next;
+        }
+        else{
+            head=head->next;
+        }
+
+        return head;
+
+    }
+};
diff --git a/Week2/Reverse_Linked_List/Anjali_Singh.cpp b/Week2/Reverse_Linked_List/Anjali_Singh.cpp
new file mode 100644
index 0000000..b094ee7
--- /dev/null
+++ b/Week2/Reverse_Linked_List/Anjali_Singh.cpp
@@ -0,0 +1,24 @@
+/**
+ * Definition for singly-linked list.
+ * struct ListNode {
+ *     int val;
+ *     ListNode *next;
+ *     ListNode() : val(0), next(nullptr) {}
+ *     ListNode(int x) : val(x), next(nullptr) {}
+ *     ListNode(int x, ListNode *next) : val(x), next(next) {}
+ * };
+ */
+class Solution {
+public:
+    ListNode* reverseList(ListNode* head) {
+        if(head==NULL)
+            return NULL;
+        if(head->next==NULL)
+            return head;
+        ListNode *ans = reverseList(head->next);
+        head->next->next=head;
+        head->next=NULL;
+        return ans;
+
+    }
+};
diff --git a/Week2/Sort_List/Anjali_Singh.cpp b/Week2/Sort_List/Anjali_Singh.cpp
new file mode 100644
index 0000000..a435a55
--- /dev/null
+++ b/Week2/Sort_List/Anjali_Singh.cpp
@@ -0,0 +1,46 @@
+/**
+ * Definition for singly-linked list.
+ * struct ListNode {
+ *     int val;
+ *     ListNode *next;
+ *     ListNode() : val(0), next(nullptr) {}
+ *     ListNode(int x) : val(x), next(nullptr) {}
+ *     ListNode(int x, ListNode *next) : val(x), next(next) {}
+ * };
+ */
+class Solution {
+public:
+    ListNode* MergeList(ListNode* hd1, ListNode* hd2){
+        if (hd1==NULL && hd2==NULL) return NULL;
+        if (hd1==NULL) return hd2;
+        if (hd2==NULL) return hd1;
+        if (hd1->val<hd2->val){
+            ///Node* nh=hd1;
+            hd1->next=MergeList(hd1->next,hd2);
+            return hd1;
+        } else {
+            hd2->next=MergeList(hd1,hd2->next);
+            return hd2;
+        }
+    }
+
+    ListNode* MidSplit(ListNode* hd){
+        if (hd==NULL||hd->next==NULL) return hd;
+        ListNode* fp=hd, *sp=hd;
+        while (fp->next!=NULL&&fp->next->next!=NULL){
+            sp=sp->next;
+            fp=fp->next->next;
+        }
+        ListNode* nh=sp->next;
+        sp->next=NULL;
+        return nh;
+    }
+    ListNode* sortList(ListNode* head) {
+        if (head==NULL||head->next==NULL) return head;
+        ListNode* nh=MidSplit(head);
+        head=sortList(head);
+        nh=sortList(nh);
+        return MergeList(head, nh);
+
+    }
+};