[Leetcode] 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).

Solution:

public class Solution {
    public int threeSumClosest(int[] num, int target) {
        Arrays.sort(num);
        int result=num[0]+num[1]+num[2];
        for (int i = 0; i < num.length - 2; ++i) {
            int low=i+1;
            int high=num.length-1;
            while(low<high){
                int sum = num[low]+num[high]+num[i];
                if(Math.abs(result-target)>Math.abs(sum-target)){
                    result=sum;
                }
                if(sum<target)
                    low++;
                if(sum>target)
                    high--;
                if(sum==target){
                    return sum;
                }
                    
            }
        }
        return result;
    }
}
原文地址:https://www.cnblogs.com/Phoebe815/p/4066365.html