The sailor stated that he had since his boyhood been engaged in trading with a small vessel among some twenty little islands in the Pacific. 
He supplied the rough chart and explained that the lines from island to island represented the only routes that he ever adopted. 
He always started from island A at the beginning of the season, and then visited every island once, and once only, finishing up his tour at the starting-point A. 
But he always put off his visit to C as long as possible, for trade reasons that I need not enter into. 
Discover his exact route, and this can be done with certainty. 
Take your pencil and, starting at A, try to trace it out. 
If you write down the islands in the order in which you visit them—thus, for example, A, I, O, L, G, etc.—you can at once see if you have visited an island twice or omitted any. 
Of course, the crossings of the lines must be ignored—that is, you must continue your route direct, and you are not allowed to switch off at a crossing and proceed in another direction.
The sailor knew the best route. 
Can you find it?

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Math Genius