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Swap the white and the black figures.
wap the black and white knights in the fewest moves
Swap the white and the black figures.
Swap the white and the black figures.
You Win!
Guarini's Problem is one of the first recreational chess problems to be posed. It is claimed to be published by mathematician Paolo Guarini di Forli in 1512, hence attribution.
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Henry E. Dudeny, centuries later, in 1917, presented this problem in regards to frogs hoping between lily pads. He credited Guarini in context of the solution.
Very little is know about Guarini himself. Thus, whether he was a real historical figure or a fictional character invented by Henry E. Dudeny himself, is yet to be discovered.
An attentive solver would notice each knight in the respective corner can move to only 2 cells adjacent to the board's perimeter. As a result the central cell is never occupied whatsoever. Thus, it can be omitted completely. But to persevere the original version of the puzzle, it is traditionally goes with the 3x3 solid board.
Let's apply some analytical reasoning steps here, which make this compact chess puzzle so intriguing after all.
Step 1
Without the central cell employed in the solution, we can say the actual board is a... single-tiled looped pathway.
Step 2
Selecting either clockwise only or counterclockwise direction and...
Step 3
...moving each knight a leap at a time...
Step 4
...alternating strictly between black and white figures...
Step 5
...would rotate the whole composition 180 degrees, making 4 loops (with one loop coating at 45 degrees) of 4 moves each and thus...
Step 6
...ending in 16 single-jump moves in total.
Yes, 16 moves! Not quite bad for such a puzzle! But the real task is: can you find such multi-jump moves along the route so that the total number of moves is decreased in half - 8 moves in total?!