AoC 2021

Day 4

Oh dear - my prediction was quite off!

Today was a challenge - I was off the global leaderboard by a chonky amount - but I believe my part 2 was notably faster than most people's (probably because my part 1 was so long!)

For Part 1, after frantically Googling 'Bingo simulator' for a minute and finding no useful results, I began coding. This was another implementation challenge with a few tricks just to help you code faster - this problem challenged your fluency in a language. One of the things I did was create a list called 'o' which just has all 10 possible rows/columns bingo lines. Getting really fluent in list comprehensions is also a huge advantage from a speed perspective! Enumerate is also surprisingly useful. Not much more to say for now, just that I wish you luck understanding my variable names...

For Part 2, I changed/added a couple of lines - replace each line that has a comment with the code after it. I used a set to keep track of which bingo cards had already 'won' (using their index relative to the input) and then just printed the score of the last card to have 'won'. The extra code here is quite self-explanatory.

Seeing how wrong my guess was yesterday, I can only hope Day 5 will be calming...