Problems from Hong Kong Regional Online Preliminary 2016

	Submissions				Users
Name	Total	Acc.	Ratio	Fastest	Total	Acc.	Ratio	Difficulty
0-1 Sequences	12920	2066	16%	0.00	2695	1445	54%	5.4
A+B Problem	10554	1017	10%	0.03	1481	485	33%	8.5
Boxes	1917	770	40%	0.06	513	426	83%	4.1
Classrooms	4197	789	19%	0.05	568	402	71%	6.4
Crazy Driver	896	345	39%	0.00	291	247	85%	4.0
Curious Cupid	1319	265	20%	0.08	200	137	68%	6.3
Dim Sum	105	39	37%	0.04	48	31	65%	7.9
k-Colouring of a Graph	219	54	25%	0.03	42	29	69%	9.0
Let's Meet	757	144	19%	0.00	105	66	63%	8.5
Palindromes	538	101	19%	0.09	140	50	36%	8.5
Take Two Stones	48813	29129	60%	0.00	24614	23646	96%	1.2