arduino to maxmsp trigger

hi there Im an audio technology student who has been using maxmsp for a little bit, but is farely new to arduino. I am currently developing a project to trigger audio files within maxmsp. The trouble i am having is with the code. Is there anyone who can help with this? I understand how to trigger in MAXMSP but im very unsure who to write this in the code. HELP :(

Thanks WKDSIDE