Sliding game
This is game to play by yourself. You will need a game board and 8 counters (or buttons or coins) - 4 of one colour and 4 of another colour.
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Place 4 counters in the top row and 4 in the bottom row. The aim is for the top counters to swap places with the bottom counters using the smallest possible number of moves. You can slide a counter one square at a time, with no jumping or sharing a square.
Record your moves so that you can count them and find the best way to solve the puzzle.
It might help to number the squares.
Image
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Click here to try an interactive version.