AC

#include<iostream>
using namespace std;
    int main(){
        int money;
        char yn;
        cin>>money>>yn;
        if(yn=='y'&&money>=1000&&money%500!=0){
            money=((money-1000)/500+1)*4+5+8;
        }
        else if(yn=='y'&&money>=1000){
            money=(money-1000)/50*4+5+8;
        }
         else if(yn=='n'&&money>=1000&&money%500!=0){
            money=((money-1000)/500+1)*4+8;
        }
        else if(yn=='n'&&money>=1000&&money){
            money=((money-1000)/500)*4+8;
        }
        cout<<money;
        return 0;
    }