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: A    B C    D

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

Posted by K Sengupta on 2005-07-05 06:17:00