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).
给定一串数,和一个目标数字,使得这串数字中其中三个元素的和最接近这个目标数字。返回最接近的和。
这道题跟上一道题很相似,也是求三个数字的和。方法也差不多,先对数组从小到大排序,然后固定一个元素,然后求另外连个元素与该元素的和最接近目标数字。
class Solution { public: int threeSumClosest(vector<int>& nums, int target) { sort(nums.begin(),nums.end()); int i=0,j,k; int min_dif=INT_MAX,difference; int a,b,c,sum,r; while(i<nums.size()){ a=nums[i]; j=i+1;k=nums.size()-1; while(j<k){ b=nums[j],c=nums[k]; sum = a+b+c; difference = sum-target; if(abs(difference)<min_dif) {r=sum;min_dif=abs(difference);} if(difference<0 && j<k) j++; if(difference>0 && j<k) k--; if(difference==0) return r; } i++; } return r; } };