Chain Shot!

SameGame (さめがめ) is a tile-matching puzzle originally released under the name Chain Shot! in 1985 by Kuniaki Moribe (Morisuke). It has since been ported to numerous computer platforms, handheld devices, and even TiVo, with new versions as of 2016.

SameGame was originally created as Chain Shot! in 1985 by Kuniaki Moribe. It was distributed for Fujitsu's FM-8 and FM-7 platforms in a Japanese monthly personal computer magazine called Gekkan ASCII. In 1992, the game was ported as SameGame to Unix platforms by Eiji Fukumoto, and to the NEC PC-9801 series by Wataru Yoshioka. In 1993, it was ported to Windows 3.1 by Ikuo Hirohata. This version was translated into English by Hitoshi Ozawa, and is still available from his software archive. In 1994, Takahiro Sumiya ported it to Macintosh. This version has some gameplay differences—three, instead of five, colors—and is probably the most widely distributed of the original series. It was the basis for the Same Gnome and KSame variations created for Linux.

In 2001, Biedl et al. proved that deciding the solvability (whether all blocks can be removed) of 1-column (or 1-row) 2-colour Clickomania can be done in linear time. Deciding the solvability of 2-column, 5-colour Clickomania is NP-Complete. Deciding the solvability of 5-column 3-colour Clickomania is also NP-Complete.

SameGame is played on a rectangular field, typically initially filled with four or five kinds of blocks placed at random. By selecting a group of adjoining blocks of the same color, a player may remove them from the screen. Blocks that are no longer supported will fall down, and a column without any blocks will be trimmed away by other columns always sliding to one side (often the left). The goal of the game is to remove as many blocks from the playing field as possible.

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