Problems from Hong Kong Regional Online Preliminary 2016

	Submissions				Users
Name	Total	Acc.	Ratio	Fastest	Total	Acc.	Ratio	Difficulty
0-1 Sequences	6889	1018	15%	0.00	1324	671	51%	6.8
A+B Problem	6646	661	10%	0.03	942	323	34%	8.1
Boxes	1331	484	36%	0.09	325	272	84%	4.2
Classrooms	1098	281	26%	0.08	235	174	74%	6.3
Crazy Driver	640	258	40%	0.00	204	177	87%	3.7
Curious Cupid	1156	208	18%	0.08	171	115	67%	5.9
Dim Sum	90	35	39%	0.04	39	27	69%	7.1
k-Colouring of a Graph	164	40	24%	0.03	31	21	68%	9.2
Let's Meet	593	113	19%	0.00	86	51	59%	8.6
Palindromes	322	77	24%	0.09	83	37	45%	7.5
Take Two Stones	25215	15263	61%	0.00	12647	12178	96%	1.3