[LeetCode16]3Sum Closed

题目来源：点击打开链接https://leetcode.com/problems/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).

class Solution16{public:int threeSumClosest(vector<int>& nums, int target){int result = 0;int min_gap = INT_MAX;sort(nums.begin(), nums.end());for (auto i = nums.begin(); i != prev(nums.end(), 2); ++i){auto j = next(i);auto k = prev(nums.end());while (j < k){int sum = *i + *j + *k;int gap = abs(sum - target);if (gap < min_gap){result = sum;min_gap = gap;}if (sum < target)++j;else --k;}}return result;}};int main16(){Solution16 solution;vector<int> nums = {-1,2,4,1};int target = 1;cout<<solution.threeSumClosest(nums, target);getchar();return 0;}