Show HN: Reverse Minesweeper

Summary

How difficulty works Every grid you generate is solved end-to-end by the same logic engine that powers the in-game hints. It plays through the whole puzzle one deduction at a time, always taking the simplest move available, exactly like a careful human, and records which reasoning techniques the grid forced it to use. There are five, and each tier is named after the hardest one the grid demands: Basic → Easy: a single clue settles its own squares: either it's already satisfied, so its remaining squares must all be empty, or it has exactly as many unknowns left as flowers it still needs. Subset → Medium: two clues compared, where every unknown one clue sees is also seen by the other. Subtracting one from the other settles the squares only the bigger clue sees. Overlap → Hard: two clues share some squares, and min/max bounds on how many flowers the shared region can hold settle the squares only one clue sees. Hard grids also always include subset moves. What-if → Extreme: cousin of Sudoku's forcing chains: hypothetically plant a flower (or a cross) in a square, follow the simple rules from there, and watch a clue break: too many flowers, or no way left to reach its number. The contradiction proves the square must be the opposite. Chains are capped at a few simple counting steps (MAX_WHAT_IF_FIRINGS), so every what-if is mentally trackable and no pencil marks are needed. Hints walk you through exactly which square to test and which clue breaks. Beyond the cap → Insane: the summit. Insane grids demand what-if chains longer than Extreme's cap (up to INSANE_CHAIN_FIRINGS counting steps), and the solver also wields the either-way technique, cousin of Sudoku colouring: try a pivot square both ways; neither hypothesis breaks anything, but both chains force the same value onto some other square, so it's proven with no contradiction at all. This is the one tier where keeping notes genuinely helps. Hints spell out both kinds: which square to test, and (for either-way) which squ...