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).
1刷
題解：
與3sum類似，先sort嗓化，然后首尾夾逼
Time complexity O(n^2), space complexityO(1)
public class Solution {
public int threeSumClosest(int[] nums, int target) {
int min = Integer.MAX_VALUE;
Arrays.sort(nums);
for(int i=0; i<nums.length-2; i++){
int lo = i+1;
int hi = nums.length-1;
while(lo<hi){
int sum = nums[i] + nums[lo] + nums[hi];
if(sum == target) return target;
else if(sum > target) hi--;
else lo++;
if(Math.abs(sum - target) < Math.abs(min)){
min = sum - target;
}
}
}
return min + target;
}
}
