Minimaxing

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In Hex, minimaxing or minmaxing means to do the minimum necessary to maintain a connection in one direction while maximizing one's strength in the other direction.

The term minimaxing as used in Hex has nothing to do with the minimax computer algorithm that is used to explore the game tree and select a move.

Example

Consider the following situation, which is fairly common in the obtuse corner.

abcde1234512

Red was connected to the bottom edge by a ziggurat, but Blue intruded into Red's connection. Where should Red play? Beginners are often eager to reconnect in the most straightforward way possible, and might play at b5:

abcde12345123

While this reconnects 1 to the edge, it doesn't do much else for Red. In fact, it even gives Blue the opportunity to play b4 and get a free 2nd row ladder escape. Where should Red play instead? Certainly b4 is a better choice. But an even better one is b3:

abcde12345312

Note that Red is connected to the edge by edge template III2a. In addition, Red has also gained significant strength towards the top. Thus, Red has done the minimum necessary to connect to the bottom (played as far away from the bottom as possible), while gaining the maximum possible strength towards the top.