#include<stdio.h>
int main() {
    int units;
    scanf("%d", &units);
    if (units < 0){
        printf("Invalid input");
        return 0;
    }
    float bill = 0;
    if (units <= 100){
        bill = units * 10;
    }
    else if(units <= 200){
        bill = 100*10+100*15+(units-200)*20;
    }
    printf("%.2f, bill");
    return 0;
    }