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---
title: '46. Permutations'
description: Given an array nums of distinct integers, return all the possible permutations. You can return the answer in any order
icon: dot
topics:
- { name: "Array", slug: "array" }
- { name: "Backtracking", slug: "backtracking" }
issue: "https://github.com/prdlk/leetcode/issues/151"
companies:
- { name: "Bloomberg", period: "Thirty Days", frequency: 69.8 }
- { name: "Amazon", period: "Thirty Days", frequency: 48.9 }
- { name: "Microsoft", period: "Three Months", frequency: 42.1 }
- { name: "Google", period: "Three Months", frequency: 32.7 }
- { name: "Infosys", period: "Six Months", frequency: 67.9 }
- { name: "LinkedIn", period: "Six Months", frequency: 54.1 }
- { name: "Meta", period: "Six Months", frequency: 43.4 }
sidebar:
label: 'Permutations'
badge: 'Medium'
---
### 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.
## Solution
```py
class Solution:
def permute(self, nums: list[int]) -> list[list[int]]:
result, path = [], []
used = [False] * len(nums)
def backtrack():
if len(path) == len(nums):
result.append(path[:])
return
for i in range(len(nums)):
if used[i]:
continue
used[i] = True
path.append(nums[i])
backtrack()
path.pop()
used[i] = False
backtrack()
return result
```