[Neos07]

ROT13 Encryption

ROT13 replaces each letter by its partner 13 characters further along the alphabet. For example, HELLO becomes URYYB (or, reversing, URYYB becomes HELLO again).

Source Code:

Public Class Form1

Dim Letter() As String = {"A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z", "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z"}
Dim Letter2() As String = {"N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z", "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m"}
Dim str As String
Private Sub EncryptButton_Click(sender As Object, e As EventArgs) Handles EncryptButton.Click
str = TextToEncryptTextBox.Text
TextToEncryptTextBox.Clear()
For i As Integer = 0 To str.Length - 1
For j As Integer = 0 To 51
If str(i) = Letter(j) Then
TextToEncryptTextBox.Text = TextToEncryptTextBox.Text + Letter2(j)
GoTo Line1
End If
Next
TextToEncryptTextBox.Text = TextToEncryptTextBox.Text + str(i)
Line1:
Next
End Sub
End Class

[Josh‎]

So that's what you were trying to do...

[Autocorrect]

So it's a Caesar cipher. Cool little tool that I suppose can be edited.

[Hiiro]

You could do something like this too:

PHP Code


<?php 
Private Shared Sub Main(args As String())
    Console.WriteLine(ROT("Hello", 13))
    Console.ReadLine()
End Sub

Public Shared Function ROT(input As String, rotation As Integer) As String
    Dim output As New StringBuilder()

    For Each chr As Char In input
        If Char.IsLetter(chr) Then
            Dim upper As Boolean = Char.IsUpper(chr)

            Dim rot__1 As Integer = Char.ToLower(chr) + rotation
            Dim min As Integer = 97, max As Integer = 122

            While rot__1 < min
                rot__1 += 26
            End While
            While rot__1 > max
                rot__1 -= 26
            End While

            output.Append(If(upper, Char.ToUpper(CChar(rot__1)), CChar(rot__1)))
        Else
            output.Append(chr)
        End If
    Next

    Return output.ToString()
End Function 


I used a code converter

[GhostCode]

That's basically a Caesar Shift with a shiftkey of 13.
A little hint:
If you want to improve it you can directly use the ascii-table to
figure out the next chars and not rely on a list of chars. :)

[$lick]

This is encoding not encryption...

[Neos07]

Thank you guys for everything!

---

You could do something like this too:

PHP Code


<?php 
Private Shared Sub Main(args As String())
    Console.WriteLine(ROT("Hello", 13))
    Console.ReadLine()
End Sub

Public Shared Function ROT(input As String, rotation As Integer) As String
    Dim output As New StringBuilder()

    For Each chr As Char In input
        If Char.IsLetter(chr) Then
            Dim upper As Boolean = Char.IsUpper(chr)

            Dim rot__1 As Integer = Char.ToLower(chr) + rotation
            Dim min As Integer = 97, max As Integer = 122

            While rot__1 < min
                rot__1 += 26
            End While
            While rot__1 > max
                rot__1 -= 26
            End While

            output.Append(If(upper, Char.ToUpper(CChar(rot__1)), CChar(rot__1)))
        Else
            output.Append(chr)
        End If
    Next

    Return output.ToString()
End Function 


I used a code converter

That's a good code thx, it's for generally ROT not just ROT13! ✌

---

That's basically a Caesar Shift with a shiftkey of 13.
A little hint:
If you want to improve it you can directly use the ascii-table to
figure out the next chars and not rely on a list of chars. :)

Thanks, i will go search about ascii-table! :)

---

This is encoding not encryption...

Can you please explain what is the difference between them?

[$lick]

Thank you guys for everything!

---

That's a good code thx, it's for generally ROT not just ROT13! ✌

---

Thanks, i will go search about ascii-table! :)

---

Can you please explain what is the difference between them?

https://danielmiessler.com/study/encodin...n_hashing/

[Neos07]

https://danielmiessler.com/study/encodin...n_hashing/

Yes, you are right, it's encoding.

[BahNahNah]

One-liner for the lolz
Spoiler (Click to View)
(i split lines so i can fit it into the screenshot ;_;)



Good work tho.
Edit: Wtf, this thread is old.

[Neos07]

One-liner for the lolz
Spoiler (Click to View)
(i split lines so i can fit it into the screenshot ;_;)



Good work tho.
Edit: Wtf, this thread is old.

It should be only one function for encoding that is in the same time decoding cuz:
f(f(x)) = x

[BahNahNah]

It should be only one function for encoding that is in the same time decoding cuz:
f(f(x)) = x

What? 😶
You need two functions.

[Neos07]

What? 😶
You need two functions.

ROT13 is an exception because it only needs one function of encoding/decoding and that because the number of letters is 26 so when yrou rotate the letter "A" it will become "N" and if you rotate "N" it will rebecome back to "A" (that's only in case of ROT13).

[MrCortex]

This is fun to see, i busy with something like this :( :P
Good work man and thanks for the share

[BahNahNah]

ROT13 is an exception because it only needs one function of encoding/decoding and that because the number of letters is 26 so when yrou rotate the letter "A" it will become "N" and if you rotate "N" it will rebecome back to "A" (that's only in case of ROT13).

So it cant keep the character case or support numbers? 😑

Heres my spin:
Spoiler (Click to View)
(Map must be a even length)