18. 4Sum

Practice 4Sum for free on NudgeCode: Medium, Two Pointers pattern. Write it in Python or JavaScript, run the tests in your browser, and ask for a hint when you are stuck.

Return all distinct quadruplets [a, b, c, d] of values from nums (using four different indices) whose sum equals target. The answer must not contain duplicate quadruplets; order doesn't matter.

Example

nums = [1,0,-1,0,-2,2], target = 0  ->  [[-2,-1,1,2],[-2,0,0,2],[-1,0,0,1]]

Constraints