Problems from 2013 ACM-ICPC North American Qualifier

	Submissions				Users
Name	Total	Acc.	Ratio	Fastest	Total	Acc.	Ratio	Difficulty
4 thought	7103	2375	33%	0.00	2386	1989	83%	2.8
Biggest Slice	753	176	23%	0.00	230	139	60%	6.8
Erratic Ants	1218	374	31%	0.00	430	313	73%	4.9
Even Up Solitaire	4157	1489	36%	0.00	1375	1116	81%	2.8
Goldbach's Conjecture	3687	1399	38%	0.00	1345	1081	80%	3.0
Island Buses	451	134	30%	0.00	141	103	73%	6.2
Oddities	21056	11527	55%	0.00	10267	9905	96%	1.4
Plotting Polynomials	255	195	76%	0.00	201	181	90%	2.6
Shotcube	313	45	14%	0.17	67	28	42%	8.7
Ternarian Weights	614	240	39%	0.00	274	226	82%	3.9
Trapezoid Walkway	452	210	46%	0.00	210	183	87%	3.4