4Sum
MediumAcceptance Rate 36.5%
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 a, b, c, d are distinct and their sum is equal to target.Examples
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]]
Constraints
0 <= nums.length <= 200-10^9 <= nums[i] <= 10^9-10^9 <= target <= 10^9