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).
思路 ： 跟 3Sum 一样
public class Solution { public int threeSumClosest(int[] num, int target) { if(num == null || num.length < 3){ return 0; } Arrays.sort(num); int result = num[0] + num[1]+ num[2]; for(int i = 0; i< num.length; i++){ int start = i+1; int end = num.length-1; while(start < end){ int tmp = num[i] + num[start]+ num[end]; if(Math.abs(target - tmp) < Math.abs(target - result)) result = tmp; if(tmp == target) return tmp; else if(tmp < target) start++; else end--; } } return result; } }
原文：http://www.cnblogs.com/RazerLu/p/3552051.html