The caesar cipher consists of an easy encode and decode.
First the shift key. The shift key is a number, any number from 1 to 25. This determines how far to go forward.
So lets use 3 as an example.
First, take the entire alphabet and think of it as a number line. The letter you start is the spot on the number line
Let's take A. If my shift key is 3, I go forward 3 but I don't begin on A. Why? This is because if I began at A, I would go only 2 letters forward. I will break it down.
If I started at A, I would only go 2 letters. (A [B C] <-- 2 letters forward) which is why I start a letter after A. (start as 0 -->A [B C D]-- go forward 3 from 0)
So the letter encoded is the letter you land on, so A is D because I went forward 3 times
But what if I do y, my shift key is 3, and there's only 1 letter after Y? I simply wrap!
So (Y Z [A B] <-- Wrap)
Therefore, once I get past Z, I go back to the beginning of the alphabet numberline.
So if I went to dogg and encoded it, it will become grjj, because my shift value is 3.
Decoding is simple. Take all of what I said, but instead of going forward on the alphabet number line, you go backwards. So D, becomes A. This is because A [B C D] becomes D [C B A]. Like going back on a number line
It's that simple!
See more! Home TT encode DoggChat using a public server