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.

題意：找到最大公共數組

目前時間復雜度O(n)，這個可以降低到log(n)，日后再優化：

java代碼：

public int maxSubArray(int[] nums) {
        int result = nums[0];
        int max = nums[0];

        for (int i = 1; i < nums.length; i++) {
            if (max + nums[i] < nums[i]) max = nums[i];
            else max = max + nums[i];
            if (max > result) result = max;
        }
        return result;
    }