leetcode #53 maximum subarray

leetcode/README.md

@@ -8,6 +8,8 @@
 |  22 | [Generate Parentheses](https://leetcode.com/problems/generate-parentheses/)                                                     | Medium      | [link](./generate_parentheses.cpp)   |
 |  35 | [Search Insert Position](https://leetcode.com/problems/search-insert-position/)                                                 | Medium      | [link](./search_insert_position.cpp) |
 |  46 | [Permutations](https://leetcode.com/problems/permutations/)                                                                     | Medium      | [link](./permutations.cpp)           |
+|  53 | [Maximum Subarray](https://leetcode.com/problems/maximum-subarray/)                                                             | Medium      | [link](./maximum_subarray.cpp)       |
+|     |                                                                                                                                 |             |                                      |
 
 
 

leetcode/maximum_subarray.cpp

@@ -0,0 +1,50 @@
+// Author: Krzysztof Bochenek
+// Email:  kpbochenek@gmail.com
+// --------------------------------
+#include <stdio.h>
+#include <vector>
+#include <unordered_map>
+#include <map>
+#include <unordered_set>
+#include <set>
+#include <stack>
+#include <math.h>
+#include <algorithm>
+#include <string>
+#include <iostream>
+
+// ---------------------
+
+typedef long long int ll;
+typedef unsigned long long ull;
+
+using namespace std;
+
+// ---------------------
+
+template<class T>
+void print_vec(const vector<T> &v, string desc = "") {
+  cout << desc << " ";
+  for (T e: v) {
+    cout << e << " ";
+  }
+  cout << endl;
+}
+
+// ---------------------
+
+class Solution {
+public:
+  int maxSubArray(vector<int>& nums) {
+    int bestMax = 0;
+    int ptMax = nums[0];
+    int currentMax = 0;
+
+    for (int n: nums) {
+      currentMax = max(currentMax + n, 0);
+      bestMax = max(bestMax, currentMax);
+      ptMax = max(ptMax, n);
+    }
+    return bestMax == 0 ? ptMax : bestMax;
+  }
+};