2019 - Problem Set - XAZXOI

	ID	Problem Show tags Hide tags	AC / Tried	Difficulty
	492	CSPJ2019B [CSP-J2019] 公交换乘 CSP-J 2019	31 / 73	5
	1621	CSPS2019A [CSP-S2019] 格雷码其他数学 2019 递归 CSP S 提高级	0 / 0	(None)
	666	666 公交换乘 (Bus Transfer) CSP-J 2019	22 / 73	6

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