Get a computer to do it, and it takes only 20 moves. A human problem-solver, however, takes about 40.
It is the solving of the Rubik's Cube, the multi-colored handheld puzzle-toy that has been entertaining and perplexing millions of people since its invention in 1974.
Now comes word that a team including researchers from more than one country has put Google's computers to work on the problem and come up with every single way that the Cube can be solved. Not only that, the computers have determined that no matter how mixed up the colored squares are, the correct solution can be found in no more than 20 turns of the cube. By contrast, scientists say, the human brain can memorize only enough algorithmically possibilities to allow for a minimum number of 40 moves. (This is on average and doesn't account for blind luck or a favorable starting point.)
This latest Rubik's Cube news comes not long after the latest world record for speed, set by a Dutchman who solved a cube in 7.08 seconds.
The typical Rubik's Cube has six sides covered with colored stickers. The colors are blue, green, orange, red, white, and yellow. When the Cube is "solved," or first thing out of the packaging, the stickers are all the same color on each side. Turning the faces of the cube mixes up the colors and creates the puzzle.
Erno Rubik of Hungary invented the Cube in 1974 and named it after himself.