080615 - Problem Set - 算道OJ

	ID	Problem Show tags Hide tags	AC / Tried	Difficulty
	18735	18735 Trainsorting Waterloo 080615	0 / 0	(None)
	18736	18736 Hot Spot Waterloo 080615	0 / 0	(None)
	18737	18737 Balance Waterloo 080615 洛谷	0 / 0	(None)

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