[18] 4Sum

https://leetcode.com/problems/4sum/description/

• algorithms
• Medium (28.49%)
• Source Code: 18.4sum.py
• Total Accepted: 184.3K
• Total Submissions: 646.9K
• Testcase Example: '[1,0,-1,0,-2,2]\n0'

Given an array nums of n integers and an integer target, are there elements a, b, c, and d in nums such that a + b + c + d = target? Find all unique quadruplets in the array which gives the sum of target.

Note:

The solution set must not contain duplicate quadruplets.

Example:

Given array nums = [1, 0, -1, 0, -2, 2], and target = 0.

A solution set is: [ [-1, 0, 0, 1], [-2, -1, 1, 2], [-2, 0, 0, 2] ]

class Solution(object):
    def fourSum(self, nums, target):
        """
        :type nums: List[int]
        :type target: int
        :rtype: List[List[int]]
        """