【leetcode】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.

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动态规划经典题，设置一个sum，不停的加A[i],每次跟记录最大值的max比较，如果大于max，就更新max；如果加上某个A[i]，sum变成小于0的数了，就把sum置成0.最后返回max即可。

代码如下：

 1 class Solution {

 2 public:

 3     int maxSubArray(int A[], int n) {

 4         int maxx = -65536;

 5         int sum = 0;

 6         for(int i = 0;i < n;i++){

 7             sum = sum+A[i];

 8             if(maxx < sum)

 9                 maxx = sum;

10             sum = sum >0?sum:0;

11         }

12         return maxx;

13     }

14 };