Given an array nums
of n integers and an integer target
, find three integers in nums
such that the sum is closest to target
. Return the sum of the three integers. You may assume that each input would have exactly one solution.
Example:
Given array nums = [-1, 2, 1, -4], and target = 1. The sum that is closest to the target is 2. (-1 + 2 + 1 = 2).
提示:sort start++ end--
答案:
class Solution { public: int threeSumClosest(vector<int>& nums, int target) { if(nums.size() <= 3) { return accumulate(nums.begin(), nums.end(), 0); } sort(nums.begin(), nums.end()); int res = nums[0] + nums[1] + nums[2]; for(int i = 0; i < nums.size() - 2; i++){ int j = i + 1, k = nums.size() - 1; while(j < k){ int sum = nums[i] + nums[j] + nums[k]; if(abs(sum - target) < abs(res - target)) res = sum; if(sum < target) j++; else k--; } } return res; } };