using System;

public class Program

{

    static bool isPrime(int x) {

        // bool is a boolean type that has value of true/false

        // please implement this method

        int i;

        for (i=2; i< (x/2) + 1; i++){

            if (x%i == 0)

            return false;

        }

        return true;

    }

    public static void Main()

    {

        int x = 101;

        bool prime = isPrime(x);

        if (prime == true)

            Console.WriteLine("{0} is a prime number.",x);

        else Console.WriteLine("{0} is not a prime number.",x);

        // please implement this program        

    }

}