Problems from KTH Challenge 2015

	Submissions				Users
Name	Total	Acc.	Ratio	Fastest	Total	Acc.	Ratio	Difficulty
A1 Paper	4299	1282	30%	0.00	1254	997	80%	3.4
Black Friday	5935	2288	39%	0.00	2285	1992	87%	2.2
Odd Binomial Coefficients	1246	386	31%	0.00	251	216	86%	3.4
Proteins	157	53	34%	0.01	52	42	81%	5.6
Shibuya Crossing	320	106	33%	0.00	95	74	78%	5.1
The Addition Game	162	20	12%	0.00	32	13	41%	9.2
Xortris	196	60	31%	0.00	68	54	79%	5.4