Given an array of integers, find a contiguous subarray which has the largest sum.

Notice

The subarray should contain at least one number.

Have you met this question in a real interview?

Yes

Example

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

1. 当遇到一个新元素时，有两个选择，包括进答案，或者从新开始统计答案

    所以当之前的元素和为负时，就从新统计答案
   
    如果不为负就继续统计答案
   

public class Solution {
    /*
     * @param nums: A list of integers
     * @return: A integer indicate the sum of max subarray
     */
    public int maxSubArray(int[] nums) {
        // write your code here
        if (nums == null || nums.length == 0) {
            return 0;
        }

        int max = Integer.MIN_VALUE;
        int sum = 0;

        for (int i = 0; i < nums.length; i++) {
            if (sum < 0) {
                sum = 0;
            }

            sum += nums[i];
            max = Math.max(max, sum);
        }
        return max;

    }
}