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Make Your Move, Kid!

This puzzle is a slight modification of Sam Loyd's Fifteen. The numbers have been replaced with letters that spell a meaningful sentence. As is well known, the solvability of a particular configuration of Fifteen depends on the parity of the number of inversions in the sequence of counters. So that if, for example, we swap the last two counters the parity of the total number of inversions changes which makes the configuration unsolvable.

In the puzzle below, pressing Reset swaps the two last counters. The task is to slide the counters (following the rules of Fifteen) so that at the end the same message is spelled: "Make Your Move, Kid!" Is this possible?

<hr> <h3> This applet requires Sun's Java VM 2 which your browser may perceive as a popup. Which it is not. If you want to see the applet work, visit Sun's website at, download and install Java VM and enjoy the applet. </h3> <hr>


  1. D.L.Silverman, Your Move, McGraw-Hill, 1971

Copyright © 1996-2008 Alexander Bogomolny