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 static void Main(string[] args)
        {
            int num, i;
              Console.WriteLine("Enter the number to check number is prime or composite");
                num=Convert.ToInt32(Console.ReadLine());
                i = 2;
                while (i <= num - 1)
                {
                    if (num % i == 0)
                    {
                        Console.WriteLine("composite number: "+num);
                        break;
                    }
                    i++;
                }
                if (i == num)
                    Console.WriteLine("prime number: " + num);
                Console.ReadLine();           
            
        }