[Python手撕]全排列
class Solution:
def permute(self, nums: List[int]) -> List[List[int]]:
res = []
n = len(nums)
def per(nums,start):
if start == n-1:
res.append(nums[:])
else:
for i in range(start,n):
nums[i],nums[start] = nums[start],nums[i]
per(nums,start+1)
nums[i],nums[start] = nums[start],nums[i]
per(nums,0)
return res