This bookcase houses a set of books wrapped in five different-colored bindings: red, blue, yellow, green, and orange. Each shelf contains one book of each color, but the color order varies from shelf to shelf.
Your challenge is to organize the books on each shelf into the same order in only three moves. Swapping the positions of two books counts as one move.
UK Version
This bookcase houses a set of books wrapped in five different-coloured bindings: red, blue, yellow, green and orange. Each shelf contains one book of each colour, but the colour order varies from shelf to shelf.
Your challenge is to get the books on each shelf into the same order in three moves. Swapping the positions of two books counts as one move.
Forget about the bottom shelf to begin with and focus on getting the top four shelves into the same order.
US Version
You should be able to arrange the top four rows of books in the same color order using just two moves.
Now you have just one move left. Can you use it to get the bottom shelf of books into the same order?
UK Version
You should be able to arrange the top four rows of books in the same colour order using two moves.
Now you have just one move left. Can you use it to get the bottom shelf of books into the same order?
US Version
The books on the first and third rows already have the same order, so there's no need to rearrange them. You can get this same order on the second shelf by switching the rightmost two books, and on the fourth shelf by swapping the book that's farthest to the left with the one second from the right.
Now there's just the problem of sorting out the bottom shelf in one move...
UK Version
The books on the first and third rows already have the same order, so there's no need to rearrange them. You can get this order on the second shelf by switching the rightmost two books, and on the fourth shelf by swapping the book that's furthest to the left with the one that's second from the right.
Now there's just the problem of sorting out the bottom shelf in one move...
Are you struggling with the last piece of the puzzle?
US Version
It doesn't matter where on each shelf the books are, as long as the color order is the same.
Take a look at the bottom shelf, and see what happens if you move the rightmost book to the far left. Just don't go swapping it with another book.
UK Version
It doesn't matter where on the shelf the books are, as long as the colour order is the same.
Have a look at the bottom shelf, and see what happens if you move the rightmost book to the far left. Just don't go swapping it with another book.
Solution
Incorrect
US Version
Too bad!
Are you making the most of each of your three moves?
UK Version
Too bad.
Are you making the most of each of your three moves?
Correct
That's right!
US Version
Nothing in the puzzle mentioned that the books had to be in the same exact positions on each shelf.
You just had to get the color order right!
UK Version
Nothing in the puzzle stipulated that the books had to be in the same positions on each shelf.
