UPDATE: If you just want to encode/decode, type -e for encode, and type -d for decode. the input "code" will still work with -d. This is a encoder/decoder I made so I can encode/decode data on my OS project. DO NOT USE FOR FREE CHAT UNLESS YOU GET PERMISSION FROM THE SCRATCH TEAM. In any case, how it works is it generates the data it needs to encode/decode messages. If you add a character to the string, it automatically will create a decoding string for it. By the way, if I need to because this could be used for free chat, I can unshare it at any time if I need to. By the way, there are some secret commands you can do when the cat asks you whether you would like to encode or decode (Look inside for what they are) Oh, and by the way, when you are decoding, if you input "code" then it will decode the last message that you encoded. I think right now that the message is "scratch cat is awesome" and the code is... the code for that. Code strings could probably consist of 2 numbers, but whatever. By the way, if you mess up on the code it used to crash, so then I made it so that for decoding it would say "CRASH!!!" and stop the project. I haven't done that for encoding yet, because I think by now (after crashing with spaces and colons) I have added all the symbols. And my computer always survived the encoding crashes, so yeah. If you find a symbol that you think it will crash on, say in the comments.
Update: TRY DECODING: 001-a 002-b 003-c 001002003-abc 003001002-cab AND SO ON: -004-d 005-e... I have seen things like this and a while ago tried to make one using a whole lotta if blocks. Now though, it adds characters to a list and their respective decode strings, so it is possible to encode a lot of messages, and you can include symbols like <>?,./'::'~` and others. I give credit to others who have made projects like this, cause I think that I first got the idea from some test chat encoding system that only the persons account and their test account could use. (C-chat or something?) Anyways, credit to them.