16. 3Sum Closest
Given an array nums of n integers and an integer target, find three integers in nums such that the sum is
closest to target. Return the sum of the three integers. You may assume that each input would have exactly
one solution.
Example:
Given array nums = [-1, 2, 1, -4], and target = 1.
The sum that is closest to the target is 2. (-1 + 2 + 1 = 2).
- Based on classic three sum
public int threeSumClosest(int[] nums, int target) {
int result = nums[0] + nums[1] + nums[2];
Arrays.sort(nums);
for(int i = 0; i < nums.length - 2; i++) {
int t = target - nums[i];
int l = i+1, r = nums.length-1;
while(l < r) {
int sum = nums[l] + nums[r];
if(sum < t) l++;
else if(sum > t) r--;
else return target;
if(Math.abs(target - sum - nums[i]) < Math.abs(target - result))
result = sum + nums[i];
}
}
return result;
}