Function return value for Main Learn programming C#

using System;
public class exercis121
{
    public static void WriteTitle(string text)
    {
        int numOfSpaces = (80 - text.Length * 2) / 2;
        text = text.ToUpper();

        // Upper line
        for (int i = 0; i < numOfSpaces; i++)
            Console.Write(" ");
        for (int i = 0; i < text.Length * 2 - 1; i++)
            Console.Write("-");
        Console.WriteLine();

        // Real title
        for (int i = 0; i < numOfSpaces; i++)
            Console.Write(" ");
        for (int i = 0; i < text.Length; i++)
            Console.Write(text[i] + " ");
        Console.WriteLine();

        // Lower line
        for (int i = 0; i < numOfSpaces; i++)
            Console.Write(" ");
        for (int i = 0; i < text.Length * 2 - 1; i++)
            Console.Write("-");
        Console.WriteLine();
    }

    public static int Main(string[] args)
    {
        if (args.Length != 1)
        {
            Console.WriteLine("What??!!");
            return 1;
        }

        WriteTitle(args[0]);

        return 0;
    }
}