動機
經典排序列舉
Problem
Given an array nums
of distinct integers, return all the possible permutations. You can return the answer in any order.
Example 1:
Input: nums = [1,2,3]Output: [[1,2,3],[1,3,2],[2,1,3],[2,3,1],[3,1,2],[3,2,1]]
Example 2:
Input: nums = [0,1]Output: [[0,1],[1,0]]
Example 3:
Input: nums = [1]Output: [[1]]
Constraints:
1 <= nums.length <= 6
-10 <= nums[i] <= 10
- All the integers of
nums
are unique.
Sol
class Solution:
def permute(self, nums: List[int], acc = []) -> List[List[int]]:
if not nums:
return [acc]
else:
return sum([self.permute(nums[:k]+nums[k+1:], acc+[nums[k]]) for k in range(len(nums))],[])