using System;

public class Program

{

    public static void Main()

    {

        Sum(5);

    }

    //6.Write a program that reads five integer numbers and prints their sum. If an invalid number is entered the program should prompt the user to enter another number(only once)

        static void Sum(int numbers)

        {

            int sum = 0;

            for (var i = 1; i <= numbers; i++)

            {

                Console.WriteLine("Please enter number " + i + ":");

                string input = Console.ReadLine();

​

                int integerInput;

                bool isInteger = int.TryParse(input, out integerInput);

​

                if (isInteger == false)

                {

                    Console.WriteLine("Enter another number");

                    continue;

                }

                else

                {

                    sum += integerInput;

​

                }

            }

            Console.WriteLine("The sum is: " + sum);

​

        }

}