Permutations II
Problem Statement - link #
Given a collection of numbers, nums
, that might contain duplicates, return all possible unique permutations in any order.
Examples #
Example 1:
Input: nums = [1,1,2]
Output:
[[1,1,2],
[1,2,1],
[2,1,1]]
Example 2:
Input: nums = [1,2,3]
Output: [[1,2,3],[1,3,2],[2,1,3],[2,3,1],[3,1,2],[3,2,1]]
Constraints #
1 <= nums.length <= 8
-10 <= nums[i] <= 10
Solutions #
class Solution {
public:
set<vector<int>> s;
void rc(vector<int>& nums, int i){
if(i == nums.size()-1){
s.insert(nums);
return ;
}
for(int j=i; j<nums.size(); j++){
swap(nums[j],nums[i]);
rc(nums,i+1);
swap(nums[j],nums[i]);
}
}
vector<vector<int>> permuteUnique(vector<int>& nums) {
vector<vector<int>> res;
rc(nums, 0);
for(auto i: s) res.push_back(i);
return res;
}
};