<p>Given a collection of numbers, <code>nums</code>,&nbsp;that might contain duplicates, return <em>all possible unique permutations <strong>in any order</strong>.</em></p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> nums = [1,1,2]
<strong>Output:</strong>
[[1,1,2],
 [1,2,1],
 [2,1,1]]
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> nums = [1,2,3]
<strong>Output:</strong> [[1,2,3],[1,3,2],[2,1,3],[2,3,1],[3,1,2],[3,2,1]]
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= nums.length &lt;= 8</code></li>
	<li><code>-10 &lt;= nums[i] &lt;= 10</code></li>
</ul>

class Solution {
public:
    void mycode(vector<int> nums, vector<vector<int>> &res,map<int,int> close,vector<int> p,int count){
    if(count==nums.size()){
        res.push_back(p);
        return;
    }
    map<int,int> close2;
    for(int i = 0 ; i < nums.size() ; i++){
        if(close2[nums[i]]==1) continue;
        if(close[i]==1) continue;
        p.push_back(nums[i]);
        close[i] = 1;
        close2[nums[i]] = 1;
        mycode(nums,res,close,p,count+1);
        close[i] = 0;
        p.erase(p.begin()+p.size()-1);
    }

}
    vector<vector<int>> permuteUnique(vector<int>& nums) {
        vector<vector<int>> res;
        map<int,int> close;
        vector<int> p;
        mycode(nums,res,close,p,0);
        return res;      
    }
};
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