Skilled human players rely mostly on heuristics and are usually able to quickly discard a great many futile or redundant lines of play by recognizing patterns and subgoals, thereby drastically reducing the search effort. Some level types can even be extended indefinitely, with each iteration requiring an exponentially growing number of moves and pushes. Sokoban is difficult not only because of its large branching factor, but also because of its large search tree depth. This is of interest for artificial intelligence (AI) research because solving Sokoban can be compared to the automated planning required by some autonomous robots. Further work showed that it was significantly more difficult than NP problems it is PSPACE-complete. The problem of solving Sokoban puzzles was first proved to be NP-hard. Sokoban can be studied using the theory of computational complexity. Different versions also exist for video game consoles, mobile phones, graphing calculators, digital cameras and electronic organizers. Implementations of Sokoban have been written for numerous computer platforms, including almost all home computer and personal computer systems. In 1988, Sokoban was published in US by Spectrum HoloByte for the IBM PC, Commodore 64, and Apple II as Soko-Ban. Sokoban was a hit in Japan where it sold more than 400,000 copies before being released in the United States. The first commercial game was published in December 1982 by Thinking Rabbit, a software house based in Takarazuka, Japan. Sokoban was created in 1981 by Hiroyuki Imabayashi. The puzzle is solved when all boxes are placed at storage locations. The number of boxes equals the number of storage locations. Boxes cannot be pulled, and they cannot be pushed to squares with walls or other boxes. To move a box, the player walks up to it and pushes it to the square beyond. The player is confined to the board and may move horizontally or vertically onto empty squares (never through walls or boxes). Some floor squares contain boxes, and some floor squares are marked as storage locations. The game is played on a board of squares, where each square is a floor or a wall.

The game was designed in 1981 by Hiroyuki Imabayashi, and first published in December 1982. 'warehouse keeper' ) is a puzzle video game in which the player pushes boxes around in a warehouse, trying to get them to storage locations. 1981 video game A Sokoban puzzle being solved.

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