max sum subarray code example

Example 1: maximum subarray solution leetcode

def approach3(nums):
    ans = nums[0]
    subarr_sum = nums[0]

    for i in range(1, len(nums)):
        subarr_sum = max(nums[i], nums[i] + subarr_sum)
        ans = max(ans, subarr_sum)

    return ans

Example 2: max subsequence sum in array

def max_subarray(numbers):
    """Find the largest sum of any contiguous subarray."""
    best_sum = 0  # or: float('-inf')
    current_sum = 0
    for x in numbers:
        current_sum = max(0, current_sum + x)
        best_sum = max(best_sum, current_sum)
    return best_sum