//输入一个职工的月薪salary，输出应交的个人所得税tax（保留两位小数） tax=rate*（salary-85）/100
//salary<=850,rate=0; 850<salary<=1350,rate=5; 1350<salary<=2850,rate=10; 2850<salary<=5850,rate=15; 5850<salary,rate=20; 
#include <stdio.h>
void main()
{
	double salary,tax,rate;
	scanf("%lf",&salary);
	if(salary<=850)
	{
		rate=0;
	}
	else 
	if(salary<=1350)
	{
		rate=5;
	}
	else
	if(salary<=2850)
	{
		rate=10;
	}
	else
	if(salary<=5850)
	{
		rate=15;
	}
	else
	{
		rate=20;
	}
	tax=rate*(salary-85)/100.0;
	printf("%lf",tax); 
	
}