#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){
        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;
}