Problems from 2013 ACM-ICPC North American Qualifier

	Submissions				Users
Name	Total	Acc.	Ratio	Fastest	Total	Acc.	Ratio	Difficulty
4 thought	6542	2215	34%	0.00	2211	1847	84%	2.8
Biggest Slice	714	169	24%	0.00	218	135	62%	6.7
Erratic Ants	1191	364	31%	0.00	422	306	73%	4.9
Even Up Solitaire	4033	1431	35%	0.00	1310	1065	81%	2.7
Goldbach's Conjecture	3632	1367	38%	0.00	1315	1053	80%	3.0
Island Buses	450	133	30%	0.00	140	102	73%	6.2
Oddities	18681	10606	57%	0.00	9453	9134	97%	1.3
Plotting Polynomials	247	191	77%	0.00	195	177	91%	2.5
Shotcube	310	42	14%	0.17	66	27	41%	8.8
Ternarian Weights	613	239	39%	0.00	273	225	82%	3.9
Trapezoid Walkway	443	208	47%	0.00	207	181	87%	3.3