一、题目

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.

二、题解

class Solution {
public:vector<vector<int>> res;vector<int> path;void backtracking(vector<int>& nums,vector<int>& used){if(path.size() == nums.size()){res.push_back(path);return;}for(int i = 0;i < nums.size();i++){if(used[i] == 1) continue;used[i] = 1;path.push_back(nums[i]);backtracking(nums,used);path.pop_back();used[i] = 0;}}vector<vector<int>> permute(vector<int>& nums) {int n = nums.size();vector<int> used(n,0);backtracking(nums,used);return res;}
};