#include<iostream>
using namespace std;

class Customer{
    public:
    void name(string name){
        cout<<name<<" ";
    
    }
};
class meter{
    public:
    int units(int unit){
        return unit;
    }
};
class Bill:public customer , public meter{
    public:
    void total(int u){
        int unit = units(u);
        int t=unit*5+50;
        cout<<t<<endl;
    }
};
int main()
{
    string name;
    int units;
    cin>>name>>units;
    if(units<0){
        cout<<"Invalid input";
        return 0;
    }
    Bill obj;
    obj.name(name);
    obj.total(units);
    return 0;
    
}