Talk:2007 USAMO Problems/Problem 4

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Solution 2 mistake

I believe Solution 2 has a mistake, or if not could be stated more formally. I'm assuming the solution means to take a spanning tree of the graph when it says to remove all the loops; that's the only way the rest of the solution could work. If I'm not mistaken, loops are edges with both endpoints the same vertex. Shouldn't the term be 'cycles'? And even with this change, it isn't obvious that one can just remove the cycles and everything will still be connected. Leoxnlin 18:36, 3 January 2009 (UTC)