LeetCode OJ：Maximum Subarray（子数组最大值）

Find the contiguous subarray within an array (containing at least one number) which has the largest sum.

For example, given the array [−2,1,−3,4,−1,2,1,−5,4],
the contiguous subarray [4,−1,2,1] has the largest sum = 6.

典型的DP问题，递推条件还是想了有点长时间，代码如下所示：

class Solution {
public:
    int maxSubArray(vector<int>& nums) {
        vector<int> ans;
        int sz = nums.size();
        if(!sz) return 0;
        ans.resize(sz);
        ans[0] = nums[0];
        int maxSum = nums[0];
        for(int i = 1; i < sz; ++i){
            ans[i] = max(nums[i], ans[i - 1] + nums[i]);　　//这里的条件应该注意
            maxSum = max(ans[i], maxSum);
        }
        return maxSum;
    }
};