Developer builds mahjong solitaire backwards to guarantee every board is solvable

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A developer has created a mahjong solitaire game that eliminates unwinnable boards by generating a solution first and then deriving the tile layout from it, rather than randomly placing tiles and hoping the result is completable. Most free online mahjong games use forward dealing, which routinely produces boards that cannot be finished — a flaw players typically discover only after spending significant time on a game. The reverse approach works by simulating a legal sequence of tile removals on an empty board and then assigning matching tile pairs to positions based on that sequence. The game also allows players to reshuffle remaining tiles at any point, ensuring no mid-game position is ever truly stuck. SVG graphics were used for tile faces to work around widespread font support gaps for Unicode's mahjong block on Windows and Android devices.

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