Number of Good Components

void dfs(vector<int>&vist,vector<vector<int>>& adj,int &count,int &sum,int node )

    {

        vist[node]=1;

        for(auto it : adj[node])

        {

            if(!vist[it])

            dfs(vist,adj,count,sum,it);

        }

        sum+=adj[node].size();

        count++;

    }

  

  

    int findNumberOfGoodComponent(int V, vector<vector<int>>& adj) {

       

       vector<int>vist(V+1,0);

       int ans=0;

       for(int i=1;i<=V;i++)

       {

           int count=0,sum=0;

           if(!vist[i]) 

           {

               dfs(vist,adj,count,sum,i);

               if(sum/2==(count*(count-1))/2||sum==0) ans++;

           }

       }

       

      return ans;

     

    }