#include<stdio.h>
#define Nmax 200000
int main()
{
 unsigned long n,k=0,i,j;
 int a[Nmax];
 scanf("%d",&n);
 for (i=2;i<=n;i++)
    a[i]=1;
 for (i=2;i<=n;i++)
      if (a[i]==1)
        {
         k++;
         for (j=2*i;j<=n;j=j+i)
            a[j]=0;
         }
  printf("Sunt %d numere prime mai mici sau egale ca %d",k,n);
  system("pause");
  return 0;
}