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In the puzzle below, the squares are colored either red, blue or white. A square may change its color, subject to the following two conditions:

  1. It is the leftmost square of the color to be replaced.
  2. Newly painted, it will become the leftmost square of its color.

To change the color, click on the square. The legal colors, if any, will rotate through the sequence red-blue-white, with illegal colors omitted. The goal of this activity is to change all the squares to the same color. At the beginning, all squares are red, so that you'd like to have them either blue or white. The starting distribution of colors may also be randomized, in which event any of the three colors can be used for the target color.

When in doubt, you may ask for help by pressing the "Suggest a move" button. Beware, though, that the algorithm used for suggestions is heavily biased toward the white color.

<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>

A few words

Copyright © 1996-2008 Alexander Bogomolny