Problems from North American Invitational Programming Contest (NAIPC) 2018

	Submissions				Users
Name	Total	Acc.	Ratio	Fastest	Total	Acc.	Ratio	Difficulty
Cut It Out!	160	69	43%	0.03	59	42	71%	6.1
Double Clique	375	98	26%	0.01	101	69	68%	6.2
Flashing Fluorescents	653	219	34%	0.00	155	123	79%	5.2
Missing Gnomes	2764	1004	36%	0.01	659	588	89%	2.6
Prefix Free Code	2083	475	23%	0.04	298	202	68%	6.8
Probe Droids	351	73	21%	0.00	88	46	52%	6.4
Rainbow Graph	101	48	48%	0.01	40	27	68%	4.2
Recovery	1140	342	30%	0.00	230	186	81%	5.3
Red Black Tree	819	340	42%	0.04	157	136	87%	4.7
Winter Festival	47	18	38%	0.07	25	16	64%	6.7
Zoning Houses	1120	347	31%	0.09	235	168	71%	6.3