<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 permute(vector<vector<int>>&finl,vector<int>nums,int l,int r){
    if(l==r){
        if(count(finl.begin(),finl.end(),nums)>0){
            return;
        }
        
        finl.push_back(nums);
        return;
    }
    for(int i=l;i<=r;i++){
        swap(nums[l],nums[i]);
        permute(finl,nums,l+1,r);
        swap(nums[l],nums[i]);
    }
}
    vector<vector<int>> permuteUnique(vector<int>& nums) {
        vector<vector<int>>finl;
        permute(finl,nums,0,nums.size()-1);
        return finl;
        
    }
};
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