algorithm notes: leetcode#53 maximum subarray

class (object):
    def maxSubArray(self, nums):
        """
        :type nums: List[int]
        :rtype: int
        """
        maxSum = leftSum = float('-Inf')
        for num in nums:
            leftSum = max(num, leftSum + num)
            maxSum = max(leftSum, maxSum)
        return maxSum

class (object):
    def maxSubArray(self, nums):
        """
        :type nums: List[int]
        :rtype: int
        """
        dp = [0] * len(nums)
        for i, val in enumerate(nums):
            dp[i] = max(val, dp[i-1]+val)
        return max(dp)