Hacker Cup 2024 Practice Round Solutions

Going through my solutions to all the problems in the Hacker Cup 2024 Practice Round. (The stream was hidden during the contest.)
My code: coming soon
Timestamps:
0:00:04 Intro
0:00:36 Problem A - Statement
0:03:00 Problem A - Analysis
0:08:25 Problem B - Statement
0:11:32 Problem B - Analysis
0:14:21 Problem C - Statement
0:17:54 Problem C - Analysis
0:33:00 Problem D1 - Statement
0:36:34 Problem D1 - Analysis
0:44:45 Problem D2 - Statement
0:48:14 Problem D2 - Analysis
1:29:23 Outro

[@davidMillerNet]

Amazing solution for D2! Beautiful. No complicated data structures. I don't think the official answer comes even close to this version. You spent extra time on your math, rather than jumping to coding.
In other words, you invested in finding a better solution with N-100 lines, rather than jumping at the default solution with N lines. It clearly paid off!

[@myst-6]

I didn't realise that the practice round ended so soon so I didn't have enough time to submit to D 😂
Thanks for this video!

[@BobJeff-x3u]

well that was a hammering jambloat wasn't it?