Problems from 2013 ACM-ICPC North American Qualifier

	Submissions				Users
Name	Total	Acc.	Ratio	Fastest	Total	Acc.	Ratio	Difficulty
4 thought	6297	2125	34%	0.00	2123	1769	83%	3.0
Biggest Slice	683	161	24%	0.00	208	129	62%	6.5
Erratic Ants	1179	358	30%	0.00	417	301	72%	4.8
Even Up Solitaire	3929	1383	35%	0.00	1273	1032	81%	2.7
Goldbach's Conjecture	3538	1330	38%	0.00	1281	1021	80%	3.1
Island Buses	440	130	30%	0.00	136	99	73%	5.9
Oddities	18207	10309	57%	0.00	9176	8866	97%	1.3
Plotting Polynomials	240	185	77%	0.00	188	171	91%	2.4
Shotcube	255	42	16%	0.17	63	27	43%	7.6
Ternarian Weights	601	233	39%	0.00	266	219	82%	3.9
Trapezoid Walkway	417	198	47%	0.00	196	171	87%	3.4