private static string CaesarCypher(string value, int shift)
char[] buffer = value.ToCharArray();
for (int i = 0; i < buffer.Length; i++)
if (Char.IsLetter(letter))
bool isLower = Char.IsLower(letter);
letter = (char)(letter + shift);
letter = (char) (letter - 26);
letter = (char) (letter + 26);
letter = (char)(letter - 26);
letter = (char)(letter + 26);
return new string(buffer);
public static void Main()
string secretMessage = @"STGML MK
Ow sjw s yjgmh gx .FWL vwnwdghwjk ozg sjw kauc sfv lajwv gx klsjlafy Nakmsd Klmvag, ujwslafy s fwo hjgbwul sfv jmffafy al, bmkl lg lwkl kaehdw ugvw gj ljq gml ksehdwk xjge glzwj vwnwdghwjk.
Lzak lggd osk afkhajwv tq zllh://bkxavvdw.fwl, ozauz ak bmkl sowkgew.
Ax qgm sjw aflwjwklwv af ogjcafy gf .FWL Xavvdw hdwskw kwfv qgmj jwkmew sfv dafck lg s ugmhdw gx qgmj twkl xavvdwk lg vglfwlxavvdw sl wflwuzkgdmlagfk vgl uge. Lzw egkl aehjwkkanw xavvdw oadd ywl lzw bgt.
zllh://ooo.wflwuzkgdmlagfk.uge";
string notSoSecretMessage = CaesarCypher(secretMessage, -18);
Console.WriteLine(notSoSecretMessage);