#include<iostream>
#include<string>
using namespace std;
class Customer{
    protected:
    string name,pass;
    public:
    void display(){
        cin>>name>>pass;
    }
};
class Meter{
    protected:
    string role;
    public:
    void display(){
        cin>>role;
    }
};
class Bill : public Meter ,public Customer{
    public:
    void result(){
        if(name.empty()||pass.empty()||role.empty()){
            cout<<"Invalid input";
            return;
        }
        cout<<name<<endl<<role;
    }
};
int main()
{
    bill.b;
    b.display();b.display1();b>result();
    return 0;
}