keys and rooms | sonu

class Solution {
public:

    void dfs(vector<vector<int>>&rooms, int node,vector<bool>&v, int &count){

        if(v[node])return;
        v[node] = true;
        count++;

        for(int i = 0; i<rooms[node].size(); i++){
            int newNode = rooms[node][i];
            dfs(rooms,newNode, v,count);
        }

    }

    bool canVisitAllRooms(vector<vector<int>>& rooms) {
      int n = rooms.size();
        vector<bool>v(n,false);
        int count = 0;
        dfs(rooms, 0, v,count);

        return count==n;
    }
};