Encryption

I’m currently working on a Encrypting Algorithm…it’s for my school project…my school teacher asked me to try it….i guess things are going really smooth….i hav already found a way to Encrypt it…but I hav a small prob decrypting back…since some ASCII values has 3 characters and some has 2…so I hav detect what letter I hav converted….at the moment I’m working on dis….i guess I’ll come up with some idea…first I’m going to take out a printout of all the ascii characters available