Problems from Hong Kong Regional Online Preliminary 2016

	Submissions				Users
Name	Total	Acc.	Ratio	Fastest	Total	Acc.	Ratio	Difficulty
0-1 Sequences	11834	1855	16%	0.00	2428	1280	53%	6.3
A+B Problem	9750	982	10%	0.03	1396	465	33%	8.1
Boxes	1791	709	40%	0.06	484	403	83%	4.2
Classrooms	3745	706	19%	0.05	511	362	71%	6.4
Crazy Driver	858	329	38%	0.00	275	233	85%	4.0
Curious Cupid	1253	240	19%	0.08	196	135	69%	6.1
Dim Sum	103	39	38%	0.04	46	31	67%	7.5
k-Colouring of a Graph	219	54	25%	0.03	42	29	69%	9.0
Let's Meet	733	143	20%	0.00	103	65	63%	8.4
Palindromes	528	96	18%	0.09	138	46	33%	8.4
Take Two Stones	45316	26961	59%	0.00	22691	21793	96%	1.4