https://leetcode.com/problems/maximum-subarray/

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

Example:

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

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.

程式碼：

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