Independent solutions, verified in code, to the monthly puzzles set by Jane Street. Each chapter states the puzzle with attribution, solves it from scratch, and closes with the program that confirms the answer. Grid-filling puzzles go to a constraint solver; the probability puzzles are derived by hand and checked by simulation.
A working draft, collecting solutions that were previously scattered as separate pieces. Ten puzzles so far: the two Block Party grids, Dancer Pairs, Well Well Well, Some Off Square, Number Hooks, Bug Byte, Beside the Point, Figurine Figuring, and the three-dimensional knight of Knight Moves 7. The mix is deliberate, since Jane Street alternates between combinatorial search, where the work is in the modelling, and probability, where the work is in finding the argument that makes the simulation unnecessary.
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