# Puzzle 54* solution - 37 parts

There seems to be an error in the virtual edition’s puzzle 54. The bits along the bottom are numbered 0 to 3, from left to right. This alternate version of the puzzle, which I’m calling 54*, is considerably harder, but still solvable (barely). See if you can solve it before peeking at my solution.

My solution

https://www.lodev.org/jstumble/?board=e0eelreeagaleerlg0fxaleell0eebgbgblelxrlelll0e0000rel_0_2

I thought it was impossible to complete this with only four red gears at first, but I managed to do some clever stuff with the bit in the lower right to make it work.

1 Like

In the Kickstarter edition of book, the bottom four bits are numbered 3-0, but the example output shows that if A=0, Bit 3 should get flipped, and if A=1, Bit 2 gets flipped, and so on. Strange that they would update the numbering, but not the solution in the back (it solves for the reverse bit order).

Anyway, mad props to you for solving the problem as written; I spent what felt like hours on it and could not.

I similarly use the virtual edition of the puzzle and have spent way too much time on this problem. In the end I found a very similar solution in 35 parts.

Solution

But they really should correct the mistake (especially if it has been pointed out 2 years ago), because it is very frustrating to spend hours on solving a problem and when finally you can compare your solution with either the book or over solutions on the forum you find out that you were not even playing the same game .

1 Like