Problems from Hong Kong Regional Online Preliminary 2016

	Submissions				Users
Name	Total	Acc.	Ratio	Fastest	Total	Acc.	Ratio	Difficulty
0-1 Sequences	8953	1321	15%	0.00	1722	861	50%	6.5
A+B Problem	8406	828	10%	0.03	1174	394	34%	8.2
Boxes	1511	589	39%	0.08	381	316	83%	4.3
Classrooms	2201	446	20%	0.08	351	260	74%	5.5
Crazy Driver	758	306	40%	0.00	246	212	86%	3.8
Curious Cupid	1211	224	18%	0.08	185	124	67%	6.3
Dim Sum	95	38	40%	0.04	43	30	70%	7.0
Let's Meet	699	134	19%	0.00	96	60	62%	8.0
Palindromes	390	83	21%	0.09	98	41	42%	8.7
Take Two Stones	33233	20031	60%	0.00	16843	16218	96%	1.3
k-Colouring of a Graph	208	50	24%	0.03	40	27	68%	8.8