47. 全排列 II/C++

跟全排列差不多
加了个set，无脑去重

class Solution {
public:
    vector<vector<int>> permuteUnique(vector<int>& nums) {
        res.clear();
        resset.clear();
        if(nums.empty())
            return res;
        
        visited=vector<bool>(nums.size(),false);
        vector<int> pe;
        generatePermute(nums,0,pe);
        
        for(auto vec:resset){
            res.push_back(vec);
        }
        
        return res;
        
    }
    
private:
    vector<vector<int>> res;
    set<vector<int>> resset;
    vector<bool> visited;
    
    void generatePermute(const vector<int>& nums, int index, vector<int>& pe){
        if(index == nums.size()){
            resset.insert(pe);
            return;
        }
        
        for(int i=0;i<nums.size();++i){
            if(!visited[i]){
                pe.push_back(nums[i]);
                visited[i]=true;
                
                generatePermute(nums,index+1,pe);
                
                visited[i]=false;
                pe.pop_back();
            }
        }
    }
};