using System;
public class Program
{
public static void Main()
//Regina Muñoz MARTÍNEZ 2B
int num;
int div = 0;
Console.WriteLine(“Write a number”);
num = int.Parse(Console.ReadLine());
for ( int i = 1; i <= num; i++)
if (num % i == 0)
div++;
}
if ( div == 2)
Console.WriteLine(“Prime number”);
else
Console.WriteLine(“Not a prime number”);