Towers of Hanoi
The Towers of Hanoi
The Towers of Hanoi is a very simple, yet interesting puzzle. You have to move all the disks to the rightmost pole, while respecting the following rules:
- In each step, all you can do is to remove exactly one disk from the top of one pole stack and place it on the top of another stack.
- You can never place a disk of larger size on top of a smaller size.
Hannah's Towers of Hanoi has three disks, as in the picture above.
However, she knows that if there were 2 disks, instead of 3, it would take her 3 steps, like this:
How to do it for 2 disks
Using this fact, can you figure out how many steps it would take for Hannah if she wanted to solve for 3 disks?
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1 solution
First do like the animation. Now you have to make 1 move with the largest disk to a free pole. After that repeat the animation by stacking on the largest disk. Hence you need 3+1+3 moves.