import java.util.Scanner;
public class Main
{
  public static void main ( String [ ] args )
  {
    Scanner input = new Scanner(System.in);
    while(true)
    {
      System.out.println("Enter an integer greater than 1");
      int n = input.nextInt();
      int composites = 1;
      int[] nums = new int[n+1];
      for(int i = 0; i <= n; i++)
      {
        nums[i] = i;
      }
      for(int i = 2; i <= (Math.sqrt(n) + 1); i++)
      {
        for(int j = i*2; j <= n; j += i)
        {
          if(nums[j] != 0)
          {
            nums[j] = 0;
            composites++;
          }
        }
      }
      if(nums[n] != 0) composites++;
      int primes = n - composites;
      System.out.println("There are " + primes + " prime numbers below " + n + "\n");
    }
  }
}