摘要：
Given a collection of numbers, nums, that might contain duplicates, return all possible unique permutations in any order. Example 1: Input: nums = [1, 阅读全文
摘要：
Given an array nums of distinct integers, return all the possible permutations. You can return the answer in any order. Example 1: Input: nums = [1,2, 阅读全文
摘要：
这是Combinations 组合项的延伸，在这里，我们允许不同的顺序出现，那么新的题目要求如下：Given two integersnandk, return all possible combinations ofknumbers out of 1 ...n.For example,Ifn= 4... 阅读全文
摘要：
The set [1, 2, 3, ..., n] contains a total of n! unique permutations. By listing and labeling all of the permutations in order, we get the following s 阅读全文
