from typing import (
    List,
)

class Solution:
    """
    @param nums: an integer array
    @param target: An integer
    @return: the difference between the sum and the target
    """
    def two_sum_closest(self, nums: List[int], target: int) -> int:
        if not nums:
            return -1

        ans = float("inf") # biggest value

        nums.sort()
        start, end = 0, len(nums) - 1
        while(start < end):
            print(ans)
            if target - (nums[start] + nums[end]) == 0:
                return 0 # early return
            elif target > (nums[start] + nums[end]): # sum is smaller than target
                ans = min(ans, target - (nums[start] + nums[end]))
                start += 1
            else: # target < (nums[start] + nums[end]) # sum is bigger than target
                ans = min(ans, (nums[start] + nums[end]) - target)
                end -= 1
        else:
            return ans