题解 | #没有重复项数字的全排列#

class Solution {
public:
    int total = 0;
    vector<vector<int> > ans;
    vector<int> temp;
    map<int,int> mp;
    void dfs(vector<int> &num,int n,int cnt){
        if(cnt == n){
            ans.push_back(temp);
            return ;
        }
        for(int i = 0;i < n;++i){
            if(!mp[num[i]]){
                mp[num[i]] = 1;
                temp.push_back(num[i]);
                dfs(num,n,cnt + 1);
                temp.pop_back();
                mp[num[i]] = 0;
            }
        }
    }
    vector<vector<int> > permute(vector<int> &num) {
        for(int i = 0;i < num.size();++i)
            mp[num[i]] = 0;
        dfs(num,num.size(),0);
        return ans;
    }
};