#include <stdio.h>
int main()

{

freopen("fractii.in","r",stdin);

freopen("fractii.out","w",stdout);

unsigned long *numitor,*numarator;

numitor=new unsigned long[1000000];

numarator=new unsigned long[1000000];

int k,n;

numarator[1]=1;numitor[1]=1;k=1;

scanf("%d",&n);

int gata=0;

while(!gata)

{gata=1;

for(int i=k;i<=k;i++)

if(numarator[i]+numitor[i]<=n)

{k++;

numitor[k]=numarator[i]+numitor[i];

numarator[k]=numarator[i];

k++;

numarator[k]=numitor[i]+numarator[i];

numitor[k]=numitor[i];

gata=0;

}

}

printf("%ld\n",k);

return 0;

}