In a game Four-in-a-Row, two players take it in turns to place counters on the board. The winner is the first player to have four adjacent counters in a line across or down (but not diagonally).
It is Black’s turn to play next. Where should she play her fourth counter to be certain of winning on her fifth turn whatever White plays?
Select one option, then click Submit.
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Select an option, then submit.
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Intermediate Mathematical Challenge 2002 (2002)
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