Problems from Hong Kong Regional Online Preliminary 2016

	Submissions				Users
Name	Total	Acc.	Ratio	Fastest	Total	Acc.	Ratio	Difficulty
0-1 Sequences	8108	1152	14%	0.00	1548	763	49%	7.0
A+B Problem	7681	744	10%	0.03	1072	354	33%	8.4
Boxes	1455	562	39%	0.08	347	294	85%	4.1
Classrooms	1601	384	24%	0.08	290	215	74%	5.8
Crazy Driver	715	286	40%	0.00	225	195	87%	3.7
Curious Cupid	1196	218	18%	0.08	178	120	67%	5.8
Dim Sum	93	36	39%	0.04	41	28	68%	7.5
k-Colouring of a Graph	186	47	25%	0.03	35	24	69%	9.0
Let's Meet	657	130	20%	0.00	93	58	62%	8.3
Palindromes	363	80	22%	0.09	93	39	42%	8.1
Take Two Stones	29666	17987	61%	0.00	15086	14528	96%	1.3