#include<iostream>
using namespace std;
class customer{
    public:
    void cName(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.cNAME(name);
    obj.total(units);
    return 0;
}