DAY7：leetcode #16 3Sum Closest

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).

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class Solution(object):
def threeSumClosest(self, nums, target):
"""
:type nums: List[int]
:type target: int
:rtype: int
"""
result = (0,0,0)
min_v = 99999
nums = sorted(nums)
for i in range(0,len(nums)-2):
j = i + 1
k = len(nums) - 1
while(True):
if j == k:
break
if nums[k] + nums[i] + nums[j] >= target:
if abs(nums[k] + nums[i] + nums[j] - target) < min_v:
result = (i,j,k)
min_v = abs(nums[k] + nums[i] + nums[j] - target)
k = k - 1
elif nums[k] + nums[i] + nums[j] < target:
if abs(nums[k] + nums[i] + nums[j] - target) < min_v:
result = (i,j,k)
min_v = abs(nums[k] + nums[i] + nums[j] - target)
j = j + 1
return nums[result[0]] + nums[result[1]] + nums[result[2]]


这道题和#15 3Sum思想一致，改变的一点就是使用一个变量存储与target最小的差。这道题只要求输出最近似的一个结果，所以只保存一个最小的差就可以了。