#include<stdio.h
int main ()
{
    int quantity;
    float total,discountRate;
    
    scanf("%d",&quantity);
    
    if(quantity < 0) {
        printf("Invalid input\n");
        return 0;
    }
    
    if(quantity >= 1 && quantity <= 5) {
        discountRate = 0.10;
    }else if (quantity >= 6 && quantity <= 10 ) {
        discount = 0.15;
    }else if (quantity > 10) {
        discountRate = 0.20;    
    }else {
        discountRate =0.0;
    }
    
    total = quantity * 100 * (1 - discountRate);
    
    printf("%.2f\n",total);
    
    return 0;
}