Permutations ii

class Solution {
public:

    void f(vector<int>& nums,vector<vector<int>> &ans,vector<int> &cur,vector<int> &visited, int n){

        if(cur.size()==n){
            ans.push_back(cur);
            return;
        }

        for(int i=0; i<n; i++){
            if(visited[i]==0){

                if(i!=0 && nums[i]==nums[i-1] && visited[i-1]==0){

                }

                else{
                    cur.push_back(nums[i]);
                    visited[i] = 1;
                    f(nums,ans,cur,visited,n);
                    visited[i] = 0;
                    cur.pop_back();
                }


            }
        }


    }

    vector<vector<int>> permuteUnique(vector<int>& nums) {
        vector<vector<int>> ans;
        vector<int> cur;
        int n = nums.size();
        vector<int> visited(n,0);
        sort(nums.begin(), nums.end());
        f(nums,ans,cur,visited,n);


        return ans;

    }
};