BST

Author: imShubh03

.vscode/settings.json

@@ -47,6 +47,7 @@
     "C_Cpp.errorSquiggles": "disabled",
     "terminal.integrated.defaultProfile.windows": "Git Bash",
     "cSpell.words": [
-        "nottake"
+        "nottake",
+        "sucessor"
     ]
 }

Binary Search Trees/B1/delete_in_BST.cpp

@@ -0,0 +1,101 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+struct TreeNode {
+    int val;
+    TreeNode* left;
+    TreeNode* right;
+    TreeNode(int x) {
+        val = x;
+        left = right = NULL;
+    }
+};
+
+class Solution {
+public:
+    TreeNode* findLastRight(TreeNode* root) {
+        while (root->right != NULL) {
+            root = root->right;
+        }
+        return root;
+    }
+
+    TreeNode* helper(TreeNode* root) {
+        if (root->left == NULL) return root->right;
+        if (root->right == NULL) return root->left;
+
+        TreeNode* rightChild = root->right;
+        TreeNode* lastRight = findLastRight(root->left);
+        lastRight->right = rightChild;
+        return root->left;
+    }
+
+    TreeNode* deleteNode(TreeNode* root, int key) {
+        if (root == NULL) return NULL;
+
+        if (root->val == key) return helper(root);
+
+        TreeNode* dummy = root;
+
+        while (root != NULL) {
+            if (key < root->val) { 
+                if (root->left != NULL && root->left->val == key) {
+                    root->left = helper(root->left);
+                    break;
+                } else {
+                    root = root->left;
+                }
+            } else { 
+                if (root->right != NULL && root->right->val == key) {
+                    root->right = helper(root->right);
+                    break;
+                } else {
+                    root = root->right;  // **Fixed: Continue moving right**
+                }
+            }
+        }
+
+        return dummy;
+    }
+};
+
+// Function to insert nodes into BST
+TreeNode* insertIntoBST(TreeNode* root, int val) {
+    if (!root) return new TreeNode(val);
+    if (val < root->val) root->left = insertIntoBST(root->left, val);
+    else root->right = insertIntoBST(root->right, val);
+    return root;
+}
+
+// Function to print inorder traversal
+void inorder(TreeNode* root) {
+    if (!root) return;
+    inorder(root->left);
+    cout << root->val << " ";
+    inorder(root->right);
+}
+
+int main() {
+    Solution sol;
+    TreeNode* root = NULL;
+
+    vector<int> values = {5, 3, 7, 2, 4, 6, 8};
+    for (int val : values) {
+        root = insertIntoBST(root, val);
+    }
+
+    int key;
+    cin >> key;
+
+    cout << "Before Deletion: ";
+    inorder(root);
+    cout << endl;
+
+    root = sol.deleteNode(root, key);
+
+    cout << "After Deletion: ";
+    inorder(root);
+    cout << endl;
+
+    return 0;
+}

Binary Search Trees/B1/floor_and_ceil_in_BST.cpp

@@ -0,0 +1,73 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+struct Node {
+    int data;
+    Node* left;
+    Node* right;
+    Node(int val) {
+        data = val;
+        left = right = NULL;
+    }
+};
+
+class Solution {
+public:
+    int floor(Node* root, int x) {
+        int floor = -1;
+        while (root) {
+            if (root->data == x) {
+                return root->data;
+            }
+            if (root->data > x) {
+                root = root->left;
+            } else {
+                floor = root->data;
+                root = root->right;
+            }
+        }
+        return floor;
+    }
+
+    int ceil(Node* root, int x) {
+        int ceil = -1;
+        while (root) {
+            if (root->data == x) {
+                return root->data;
+            }
+            if (root->data < x) {
+                root = root->right;
+            } else {
+                ceil = root->data;
+                root = root->left;
+            }
+        }
+        return ceil;
+    }
+};
+
+// Function to insert a node into BST
+Node* insertIntoBST(Node* root, int val) {
+    if (!root) return new Node(val);
+    if (val < root->data) root->left = insertIntoBST(root->left, val);
+    else root->right = insertIntoBST(root->right, val);
+    return root;
+}
+
+int main() {
+    Solution sol;
+    Node* root = NULL;
+    vector<int> values = {10, 5, 15, 3, 7, 18}; 
+    
+    for (int val : values) {
+        root = insertIntoBST(root, val);
+    }
+
+    int x;
+    cin >> x;
+
+    cout << "Floor: " << sol.floor(root, x) << endl;
+    cout << "Ceil: " << sol.ceil(root, x) << endl;
+
+    return 0;
+}