// editor4
#include<stdio.h>
int main(){
    int quality;
    float total, discountRate;
    
    scanf("%d", &quality);
    
    if (quantity < 0){
        printf("Invalid input\n");
        return 0;
    }
    
    if (quantity >=1 && quantity <=5){
        discountRate = 0.10;
    } else if (quantity >= 6 && quantity <= 10){
        discountRate = 0.15;
    }else if(quantity > 10){
        discountRate = 0.20;
    }else {
        discountRate = 0.0;
    }
    total = quantity * 100 *(1 - discountRate);
    
    printf("%.2f\n" , total);
    return 0;
}