#include <cstdio>
#include <vector>
using namespace std;
int main()
{
	freopen ("fractii.in","r",stdin);
	freopen ("fractii.out","w",stdout);
	
	int n,anz=1,anf=1,x,i,j;
	bool fertig=false;
	vector <int> bruche (3);
	bruche[1]=1;
	bruche[2]=1;
	
	scanf ("%d",&n);
	
	while (fertig==false)
	{
		x=bruche.size();
		for (int t=anf;t<x;t+=2)
		{
			i=bruche[t];
			j=bruche[t+1];
			if ((i+j)<=n)
			{
				anz+=2;
				bruche.push_back(i+j);
				bruche.push_back(j);
				bruche.push_back(i);
				bruche.push_back(i+j);
			}
			else
				fertig=true;
		}
		anf=anf*2+1;
	}

	printf ("%d", anz);
	
	return 0;
}