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

public class Solution {
    /**
     * @param nums: A list of integers
     * @return: A integer indicate the sum of max subarray
     */
    public int maxSubArray(ArrayList<Integer> nums) {
        if (nums == null || nums.size() == 0) return 0;

        int local = 0, max = Integer.MIN_VALUE;
        for (int num : nums) {
            local = Math.max(local + num, num);//num must be the last number in local
            max = Math.max(max, local);
        }
        return max;
    }
}

class Solution(object):
    def maxSubArray(self, nums):
        """
        :type nums: List[int]
        :rtype: int
        """

        if not nums:
            return 0

        global_max, local_max = - 2 ** 31, 0
        for num in nums:
            local_max = max(num, num + local_max)
            global_max = max(global_max, local_max)
        return global_max