def max_sub_array(nums):
    # Initialize variables to keep track of the current subarray sum and the maximum subarray sum.
    current_sum = nums[0]
    max_sum = nums[0]

    # Iterate through the array starting from the second element.
    for i in range(1, len(nums)):

        # Calculate the current subarray sum by considering two possibilities:
        # 1. The current element creates a new subarray with a higher sum (nums[i] itself).
        # 2. The current element extends the subarray ending at i-1 with the current element.
        current_sum = max(nums[i], current_sum + nums[i])

        # Update the maximum subarray sum seen so far.
        max_sum = max(max_sum, current_sum)

    # Return the maximum subarray sum.
    return max_sum

# Driver code
def main():
    inputs = [[1, 2, 2, 3, 3, 1, 4], [2, 2, 1], [4, 1, 2, 1, 2], [-4, -1, -2, -1, -2], [25]]

    for i in range(len(inputs)):
        print(i + 1, ".\tArray: ", inputs[i], sep="")
        print("\tResult: ", max_sub_array(inputs[i]), sep="")
        print("-" * 100)


if __name__ == "__main__":
    main()