problem18

README

< Previous 　　　　　　　　　　　　　　　　 Next >

18. 4Sum (Medium)

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]
]

Related Topics

[Array] [Hash Table] [Two Pointers]

Similar Questions

1. Two Sum (Easy)
2. 3Sum (Medium)
3. 4Sum II (Medium)