[Shorel]

In this modern time, no one needs to know what the ASCII code for @ is, but I think it is logical to expect people to know that some encoding exists and that letters can be mapped to numbers.

Also, all the ASCII you need to know to solve the problem is explained at length in the problem description.

[jniedrauer]

I couldn't tell you offhand how to convert between an int and an ASCII character.

...But if you give me a second...

Now that I've typed "ascii character codes" into google, I can tell you how to convert between an int and a character.

You don't have to memorize everything. Well over half of our job is knowing how to find information quickly.