g0001_0100.s0018_4sum.readme.md Maven / Gradle / Ivy
18\. 4Sum
Medium
Given an array `nums` of `n` integers, return _an array of all the **unique** quadruplets_ `[nums[a], nums[b], nums[c], nums[d]]` such that:
*   `0 <= a, b, c, d < n`
*   `a`, `b`, `c`, and `d` are **distinct**.
*   `nums[a] + nums[b] + nums[c] + nums[d] == target`
You may return the answer in **any order**.
**Example 1:**
**Input:** nums = [1,0,-1,0,-2,2], target = 0
**Output:** [[-2,-1,1,2],[-2,0,0,2],[-1,0,0,1]] 
**Example 2:**
**Input:** nums = [2,2,2,2,2], target = 8
**Output:** [[2,2,2,2]] 
**Constraints:**
*   `1 <= nums.length <= 200`
*   -109 <= nums[i] <= 109
*   -109 <= target <= 109    © 2015 - 2025 Weber Informatics LLC | Privacy Policy