16. 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).

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public class Solution {    public int threeSumClosest(int[] nums, int target) {        int min = Integer.MAX_VALUE;int re = 0;Arrays.sort(nums);for (int i = 0; i < nums.length - 2; ++i) {if (i == 0 || nums[i] != nums[i - 1]) {int lo = i + 1;int hi = nums.length - 1;while (lo < hi) {int gap = target - nums[i] - nums[lo] - nums[hi];if (gap == 0)return target;if (min > Math.abs(gap)) {min = Math.abs(gap);re = nums[i] + nums[lo] + nums[hi];}if (gap > 0)lo++;elsehi--;}}}return re;    }}