#include<stdio.h>
int main(void)
{
int a;
scanf("%d",&a);
double b;
if(a>=0&&a<=180)
{
b=a0.56;
printf("%.2f",b);
}
else if(a>180&&a<=260)
{
b=180*0.56+(a-180)*0.61;
printf("%.2f",b);
}
else if(a>260)
{
b=1800.56+80*0.61+(a-260)*0.86;
printf("%.2f",b);
}
return 0;
}

