This simple problem teaches three important lessons: Output must be exact. Computers don't understand "close enough". Every character matters, including spaces and punctuation.
Read problems carefully. The specification tells you exactly what to print. Don't assume or improvise.
Test before submitting. Run your code locally first. If it looks right in your terminal, it'll likely pass on HackerRank. These habits scale to harder problems. A complex algorithm with wrong output format still fails. Precision matters from day one.