import java.util.*;
public class Prime {
  
  
  public static void main(String[] args) { 
    
    Scanner input = new Scanner(System.in);
    
    System.out.print("Enter a positive integer: ");
    
    long number = input.nextLong();
    
    if(number<=0) {
      System.err.println("Must enter a positive number.");
      System.exit(1);
    }
    /*
    //Take 1: Try all possible divisors
    
    boolean isPrime = true;
    for(int divisor = 2; divisor < number; divisor++) {
      if(number % divisor ==0) {
        isPrime = false;
      }
    }
    */
    
    //Take 2: When you find the answer, stop
    boolean isPrime = true;
    for(long divisor = 2; divisor < number; divisor++) {
      if(number % divisor ==0) {
        isPrime = false;
        break;
      }
    }
    /*   
    //or
     boolean isPrime = true;
    for(int divisor = 2; divisor < number && isPrime; divisor++) {
      if(number % divisor ==0) {
        isPrime = false;
      }
    }
    
    //Take 3: If a number has a divisor (other than 1 and itself), it has 
    //at least 1 divisor <=its square root. So if you pass sqrt(number) and
    //have not yet found a divisor, you will not ever find one. 
    
    
    boolean isPrime = true;
    for(long divisor = 2; divisor * divisor <= number; divisor++) {
      if(number % divisor ==0) {
        isPrime = false;
        break;
      }
    }
    
    //14 = 2 , 7
    //18 = 2, 3, 6, 9
    //49 = 7
    */
    
    System.out.println(isPrime);
    
  }
  
  
  
}