#include <stdio.h>
int diao = 0;
void giao(int a)
{
	int z;
	if (a > 1)
	{
		diao = diao + 1;
		/*printf("%d\n", a);*/
	}
	if (a == 1)
	{
		diao = diao + 1;
	/*	printf("%d\n", a);*/
	}
	z = a / 2;	
	if (z == 0)
		return ;
	for (int i = z; i > 0; i--)
	{
	/*	printf("%d\n", i);*/
		giao(i);
	}
}
	int main()
	{
		int n;
		scanf("%d",&n);
		giao(n);
		printf("%d", diao);
	}