#include <stdio.h>

int main()
{
    int a, sum;
    while (scanf("%d", &a) == 1)
    {
        if (a >= 0 && a <= 10)
        {
            sum = a * 6;
            printf("%d\n", sum);
        }
        else if (a >= 11 && a <= 20)
        {
            sum = 60 + (a - 10) * 2;
            printf("%d\n", sum);
        }
        else if (a >= 21 && a <= 40)
        {
            sum = 80 + (a - 20);
            printf("%d\n", sum);
        }
        else if (a > 40)
        {
            sum = 100;
            printf("%d\n", sum);
        }
    }

    return 0;
}