[leetcode]47. Permutations II

链接：https://leetcode.com/problems/permutations-ii/description/

Given a collection of numbers that might contain duplicates, return all possible unique permutations.

Example:

Input: [1,1,2]
Output:
[
  [1,1,2],
  [1,2,1],
  [2,1,1]
]

class Solution {
public:
    vector<vector<int>> permuteUnique(vector<int>& nums)  {
        vector<vector<int>> result;
        vector<int> tmp;
        vector<int> visited(nums.size(), 0);
        sort(nums.begin(), nums.end());
        dfs(nums,result,tmp,visited);
        return result;
    }
    void dfs(vector<int> &nums,vector<vector<int>> &res,vector<int> tmp,vector<int> visited)
    {
        if(tmp.size()==nums.size())
        {   if (find(res.begin(), res.end(), tmp) == res.end())
                res.push_back(tmp);
            return;
        }
        for(int i=0;i<nums.size();i++)
        {
    
            if (visited[i] == 0) 
            {
                tmp.push_back(nums[i]);
                visited[i] = 1;
                dfs(nums,res,tmp,visited);
                tmp.pop_back();
                visited[i] = 0;
            }
        }
 
        
    }

};