Problems from 2013 ACM-ICPC North American Qualifier

	Submissions				Users
Name	Total	Acc.	Ratio	Fastest	Total	Acc.	Ratio	Difficulty
4 thought	5530	1873	34%	0.00	1876	1562	83%	3.1
Biggest Slice	652	157	24%	0.00	200	126	63%	6.4
Erratic Ants	994	292	29%	0.00	367	264	72%	4.9
Even Up Solitaire	3652	1225	34%	0.00	1149	921	80%	2.8
Goldbach's Conjecture	3306	1212	37%	0.00	1191	933	78%	3.5
Island Buses	424	124	29%	0.00	130	94	72%	6.1
Oddities	16294	9276	57%	0.00	8325	8047	97%	1.3
Plotting Polynomials	233	179	77%	0.00	182	165	91%	2.4
Shotcube	250	41	16%	0.17	61	26	43%	8.0
Ternarian Weights	586	226	39%	0.00	260	214	82%	3.9
Trapezoid Walkway	347	181	52%	0.00	179	158	88%	3.2