Maximum Subarray

Problem Statement - link #

Given an integer array nums, find the contiguous subarray (containing at least one number) which has the largest sum and return its sum.

A subarray is a contiguous part of an array.

Examples #

Example 1:

Input: nums = [-2,1,-3,4,-1,2,1,-5,4]
Output: 6
Explanation: [4,-1,2,1] has the largest sum = 6.

Example 2:

Input: nums = [1]
Output: 1

Example 3:

Input: nums = [5,4,-1,7,8]
Output: 23

Constraints #

• 1 <= nums.length <= 105
• -104 <= nums[i] <= 104

Follow up: If you have figured out the O(n) solution, try coding another solution using the divide and conquer approach, which is more subtle.

Solutions #

class Solution {
public:
    int maxSubArray(vector<int>& nums) {
      int res = nums[0];
      int temp = res;
      for(int i=1; i<nums.size(); i++){
        temp = max(temp+nums[i], nums[i]);
        res = max(res, temp);
      }
        
      
      return res;
    }
};