You have a square 5 x 5 board with four rooks in the corners:
Note: for reference, assume the rooks are labeled A, B, C, D as follows:
You can move the rooks horizontally or vertically. The only problem is that when you move a rook, it will keep going in the same direction until it hits another rook or the edge of the board.
You want to move a rook into the darkened square on the board.
How can this be done in no more than 10 moves?
Let us denote a movement to the right and a movement to the left respectively by R and L. The donward and upward movement are denoted respectively by D and U.
Then, the rook can be moved in the specified position in terms of the following moves:
1. C- R- D5,
2. B- L - B1,
3. A-D - A5,
4. D -U - E1,
5. A- R -C5,
6. D-L- C1,
7. B-D- B5,
8. A - U -C2,
9. B- L- C5,
10. B -U-C3.
Edited on April 30, 2007, 12:27 pm