CTF Event
Leo's 20th Birthday Bash
Dec 12–13, 2026
about
Hey! You there! Do you like programming? Do you like puzzles? Do you like... money? Leo's 20th Birthday Bash is a 24-hour online team contest that's competitive-programming-ish, CTF-ish, math-olympiad-ish, and puzzle-hunt-ish, all wrapped into one. The contest runs on DMOJ, an online judge for competitive programming, and each team shares one DMOJ account to submit from. Teams can have 1 to 10 members (6 to 8 recommended). Some problems are CTF-ish, but DMOJ itself is not part of the contest, so please do not attack, probe, or abuse it. The people at DMOJ are hosting this for free >.< This contest has no sponsors, so all the prize money is from yours truly ;) Make sure you've read all the rules (see the contest page). In particular, interactive generative AI is not allowed, because it is s
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