#include<stdio.h>
int main()
{
    int a;
    scanf("%d",&a);
    if (a<0)
    {
        printf("Invalid input");
    }
    else
    float b=a*100 ;
    if (a<=5) b*=0.9;
    else if (a<=10) b*=0.85;
    else
    b*=0.8;
    printf("%.2f",b);
    
}