#include<fstream.h>

long c,n,a,d,b,nr;
char v[1000000],gasit;

int main()
{
 ifstream f("ciur.in");
 ofstream g("ciur.out");
 f>>n;
 nr=1;
 d=3;
 while(d<=n)
  {
   a=d;b=d<<1;
   while(a<=n){c=a>>1;if(!v[c]){v[c]=1;nr++;}a+=b;}
   gasit=0;c=d>>1+1;
   while(!gasit)
   {
    if(!v[c]){d=c<<1+1;gasit=1;}
    else c++;
    }
   }
 g<<nr;
 return 0;
 }