The "Rubik's Mirror Blocks" puzzle.
See also the "Rubik", "Cube21", and "GLSnake" screen savers.
-http://en.wikipedia.org/wiki/Combination_puzzles#Irregular_cuboids
+https://en.wikipedia.org/wiki/Combination_puzzles#Irregular_cuboids
Written by Vasek Potocek; 2009.
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