Problems from Hong Kong Regional Online Preliminary 2016

	Submissions				Users
Name	Total	Acc.	Ratio	Fastest	Total	Acc.	Ratio	Difficulty
0-1 Sequences	10012	1505	15%	0.00	1987	1029	52%	5.8
A+B Problem	8771	863	10%	0.03	1230	411	33%	8.3
Boxes	1563	617	39%	0.06	403	335	83%	4.2
Classrooms	3203	600	19%	0.05	421	294	70%	6.2
Crazy Driver	810	315	39%	0.00	260	221	85%	3.9
Curious Cupid	1217	231	19%	0.08	187	127	68%	6.3
Dim Sum	95	38	40%	0.04	43	30	70%	7.0
k-Colouring of a Graph	208	50	24%	0.03	40	27	68%	8.8
Let's Meet	710	135	19%	0.00	97	61	63%	8.0
Palindromes	393	83	21%	0.09	99	41	41%	8.8
Take Two Stones	36507	21862	60%	0.00	18461	17750	96%	1.4