#include<stdio.h>
struct book
{
    int n;
};
int main()
{
    struct book a;
    scanf("%d",&a.n);
    if(a.n<0)
    {
        printf("Invalid input");
    };
    else if(a.n<6&&a.n>0)
    {
        float a=((a.n*100)*(1.0-0.10));
        printf("%2f",a);
    };
    else if(a.n<11&&a.n>5)
    {
        float b=((a.n*100)*(1.0-0.15));
        printf("%2f",b);
        else if(a.n>11)
        {
            float c=((a.n*100)*(1.0-0.20));
            printf("%2f",c);
        }
        else
        {
            printf("Invalid input");
        }
    }
        return 0;
    
}