codinghard

Enclose blzh

spbctf

Task: Grid puzzle game where walls are placed to enclose a hedgehog, solving 10 levels within 60 seconds with a wall budget constraint. Solution: Exploit a TOCTOU race condition in the API to place budget+1 walls, combined with region growing/shrinking and simulated annealing heuristics for optimal wall placement.

$ ls tags/ techniques/
race_conditiontoctouoptimizationapithreadingspeedrungrid_puzzle
toctou_race_conditionregion_growingregion_shrinkingsimulated_annealingbarrier_synchronization
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