CodeJam Round 1B Recap

Code Jam gcj2021

I got the confirmation email some time ago, I’m good to go for round 2. Here are the individual problems’ write-ups, in case you missed them.

I’m not exactly proud of how I passed, but not needing to make myself available for round 1C was greatly appreciated for my local lockdown logistics’ planning.

I had the right approach from the start for Broken Clock—and think the ones in the analysis are overengineered, FTM—but took way too long to push it past the finish line. Pressure and stupidly ridiculous bugs. Oh well.

I had Subtransmutation mostly up in time. Just a wee bit overengineered, which cost me not passing the large set in time. Simplifying binary search down to linear search got it to pass with less than five minutes of thinking past round end. Oh well.

I didn’t get a chance to poke at Digit Blocks much further than reading the statement. Hypothetically, assuming I’d tackled the problems in another order, I definitely would have completed the greedy put-nines-on-top strategy, then intuited DP and failed to simplify to the top-N. Would I have fallen back to top-2-rows-based heuristics and succeeded there? I have no idea.

There’s a bit over a week to round 2. Will I manage to carve out some time to upsolve the other round 1 problems before then? There’s only one way to find out!