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).
和3sum几乎一样
class Solution { public int threeSumClosest(int[] nums, int target) { if(nums.length < 3) return 0; int result = nums[0] + nums[1] + nums[nums.length-1]; int ab = Math.abs(result - target); Arrays.sort(nums); for(int i = 0; i < nums.length-2; i++){ int left = i+1, right = nums.length-1; while(left < right){ int cur = nums[i] + nums[left] + nums[right]; int cur_ab = Math.abs(cur-target); if(cur_ab < ab){ ab = cur_ab; result = cur; } if(target > cur)left++; else if(target<cur)right--; else return cur; } } return result; } }