LeetCode 16.3Sum Closest

题目描述：

Given an array S of n integers, find three integers in S such that the sum is closest to a given number, target. Return the sum of the three integers. You may assume that each input would have exactly one solution.

For example：

given array S = {-1 2 1 -4}, and target = 1.The sum that is closest to the target is 2. (-1 + 2 + 1 = 2).

AC代码：

class Solution(object):    def threeSumClosest(self, nums, target):        """        :type nums: List[int]        :type target: int        :rtype: int        """        nums.sort()        result = []        for i in range(len(nums) - 2):            l, r = i + 1, len(nums) - 1            while l < r:                sums = nums[i] + nums[l] + nums[r]                diff = sums - target                if diff == 0:                    return target                elif diff < 0:                    result.append(diff)                    l += 1                else:                    result.append(diff)                    r -= 1        result.sort()        if result[0] > 0:            return target + result[0]        elif result[-1] < 0:            return target + result[-1]        else:            for i in range(len(result)):                if result[i] < 0 < result[i + 1]:                    if abs(result[i]) < result[i + 1]:                        return target + result[i]                    else:                        return target + result[i + 1]