3Sum Closest
Difficulty: Medium
Category: DSA
Topics: Array, Two Pointers, Sorting
Asked at: Amazon, Apple, Google, Facebook, Bloomberg
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`
- `-104 <= target <= 104`