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).
Answer:
public int threeSumClosest(int[] nums, int target) {
Arrays.sort(nums);
int res = 0, min = Integer.MAX_VALUE;
for(int i=0; i < nums.length; ++i){
int j = i+1;
int k = nums.length - 1;
while(j < k){
int sum = nums[i] + nums[j] + nums[k];
int diff = Math.abs(sum - target);
if( diff < min){
min = diff;
res = sum;
}
if(sum < target){
j++;
}else{
k--;
}
}
}
return res;
}