Print the illustration and have three counters marked A, three marked B, and three marked C. 
At the intersection of lines there are nine stopping-places, and a tenth stopping-place is attached to the outer circle like the tail of a Q.
Place the three counters or engines marked A, the three marked B, and the three marked C at the places indicated.
 Move the engines, one at a time, along the lines, from stopping-place to stopping-place, until you succeed in getting an A, a B, and a C on each circle, and also A, B, and C on each straight line. 
You are required to do this in as few moves as possible. 
How many moves do you need?

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Math Genius