Blueberry, can you update your first post and tell us which errors you have found and fixed so far? If you fix a few I'll give you more pointers.

Did you already found out what you need to change that double diamond operator to read from STDIN?

Sorry we make you sweat a little... we want you to learn in the process... and that takes some effort. Maybe team up with another classmate?

TIP: Go line by line. Write only the first line, run the perl script. If it runs, add another line, run again...