3Sum Closest

Medium

Two Pointers

Given an integer array nums of length n 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 1

Input: nums = [-1,2,1,-4], target = 1

Output: 2

Explanation: The sum that is closest to the target is 2. (-1 + 2 + 1 = 2).

Example 2

Input: nums = [0,0,0], target = 1

Output: 0

Explanation: The sum that is closest to the target is 0. (0 + 0 + 0 = 0).

Constraints

•3 <= nums.length <= 500
•-1000 <= nums[i] <= 1000
•-10^4 <= target <= 10^4

Show Hints (3)

Hint 1: Sort the array first, then use a similar approach to 3Sum.

Hint 2: For each fixed element, use two pointers to find the pair that makes the sum closest to target.

Hint 3: Track the closest sum seen so far and update it whenever you find a closer one.

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Test Results

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