Im desperate here I have been working on this hashing program and im really bad at multiple files I followed all the rules in books and web pages I have seen on the topic and still cant get it to compile =(. I have included my 3 files I also use dev C++ if that helps. I appreciate this very much.

If you have it all in one file like that you need the hash.h portion up top, followed by the hash.cpp portion, followed by the main.cpp portion (and take out the hash.cpp/hash.h code you have pasted directly into main). The hash.cpp portion could be after the main program instead if you wanted. It's important that the main function and the definition of the hash methods "know" about the declaration of the class, hence it must go up top.

Otherwise, including hash.h in main.cpp and compiling as a project (since you have Dev) with hash.cpp or at the commandline as g++ hash.cpp main.cpp -o yourfilenamehere should do the trick.