leetcode Maximum Subarray

题目：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.

找一个子串的和最大。返回最大值。据说叫做动态规划。几行就搞定了。就是max和sum比大小，sum的取值是，如果之前wei负数，直接去除，如果不为负数就加上当前的数再和max比较。

class Solution {
public:
    int maxSubArray(int A[], int n) {
        // Start typing your C/C++ solution below
        // DO NOT write int main() function
        int sum = A[0], max = A[0];
        for (int i = 1; i < n; i++) {
            sum = sum < 0 ? A[i] : sum + A[i];
            max = sum > max ? sum : max;
        }
        return max;
    }
};

 这个哥们写了好多。