#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 ) {
        discounrate = 0.15;
    } else if (quantity > 10) {
        discountrate = 20;
    } else {
        discountrate = 0.0;
    }
    total = quantity * 100 * (1 - discountrate);
    printf("%.2f\n",total);
    
    return 0;
    
}