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LeetCode-18. 4Sum #27

Closed ninehills closed 6 years ago

ninehills commented 7 years ago

问题

https://leetcode.com/problems/4sum/tabs/description Given an array S of n integers, are there elements a, b, c, and d in S 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.

For example, given array S = [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]
]

思路

解答

ninehills commented 7 years ago

4 20170727