#include <iostream>
using namespace std;
int calc(int n){
if(n<=500){
return n*0.7;
}
else if(n>500 && n<=1500){
return 350+(n-500)*0.4;
}
else if(n>1500 && n<=4500){
return 750+(n-1500)*0.15;
}
else if(n>4500 && n<=10000){
return 1200 + (n-4500)*0.05;
}
else{
return 1475 + (n-10000)*0.02;
}
}
int main(){
int num;
cin >> num;
int ans = calc(num);
cout << ans;
}