Import necessary libraries
You should add a setup() function.
Use Serial.print() instead of cout
Maybe even read:
Read this before posting a programming question ... - #18 by nickgammon.._gaMTk1NDExNzgzMi4xNzUyMTY4Njcy*_ga_NEXN8H46L5*czE3NTIxNjg2NzIkbzEkZzAkdDE3NTIxNjg2NzIkajYwJGwwJGgzNjUxNDg5MTM.