[Leetcode] (python): 046-permutations

Source of the topic

https://leetcode.com/problems/permutations/

Given A collection of distinct numbers, return all possible permutations.

For example,
[1,2,3]The following permutations:
[1,2,3],,,,, [1,3,2] [2,1,3] [2,3,1] [3,1,2] and [3,2,1] .

Test instructions Analysis

INPUT:A List

Output:a permutations

Conditions: Full arrangement

Topic ideas

Recursive resolution. Note that Python takes a few bits of the list easily, shards ~ and then carefully discovers not only the full sort, but also the dictionary order (because each iteration is small to large, the traversal order depends on ~)

AC Code (PYTHON)

1 classsolution (object):2     defpermute (Self, nums):3         """4 : Type Nums:list[int]5 : Rtype:list[list[int]]6         """7         ifLen (nums) = = 1:8             return[Nums]9res = []Ten          forIinchRange (len (nums)): One              forJinchSelf.permute (Nums[:i] + nums[i+1:]): ARes.append ([nums[i]] +j) -         returnRes

[Leetcode] (python): 046-permutations