#include <stdio.h>
int main(void)
{
    double x;
    double y;
    while (1)
    {
        printf("input:");
        scanf("%lf",&x);
        if (x<1)
        {
            y = x;
        }
        else if (x>=1 && x<10)
        {
            y = 2*x-1;
        }
        else if (x>=10)
        {
            y = 3*x-11;
        }
        printf("output: %10.5lf\n",y);
    }
}