#include <stdio.h>
#include <math.h>

int main()
{
	double L, p, x, p2;
	int intx;
	double PId2 = asin(1);
	while (scanf("%lf", &L) != -1)
	{
		if(L <= 1.0)
		{
			p = L / PId2;
		}
		else
		{
			x = asin(1.0 / L);
			p = L / PId2 *(1 - cos(x));
			p += (PId2 - x) / PId2;
		}
		
		intx = (int) (p * 1000);
		
		p2 = (1 - p) * (intx + 1) / (p * (1000 - intx));
		if (p2 > 1)
		{
			printf("%d\n", intx);	
		}
		else
		{
			printf("%d\n", intx+1);	
		}	
	}
	return 0;
}