53. Maximum Subarray

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.
题目：最大子序列和，任何一本算法书都会有这个例子。

class Solution {public:    int maxSubArray(vector<int>& nums) {        int cursum = 0, maxsum, sz = nums.size();        maxsum = nums[0];        for(int i = 0; i < sz; ++i){            cursum += nums[i];            if(cursum > maxsum)                maxsum = cursum;            if(cursum < 0){                cursum = 0;            }         }        return maxsum;    }};