#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("%d2f",a);
   }
   else if(a.n<||&&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;
   }
}