Problems from KTH Challenge 2015

	Submissions				Users
Name	Total	Acc.	Ratio	Fastest	Total	Acc.	Ratio	Difficulty
A1 Paper	4160	1246	30%	0.00	1215	964	79%	3.6
Black Friday	5824	2245	39%	0.00	2239	1949	87%	2.2
Odd Binomial Coefficients	1243	383	31%	0.00	249	214	86%	3.3
Proteins	156	52	33%	0.01	51	41	80%	5.6
Shibuya Crossing	319	105	33%	0.00	94	73	78%	5.1
The Addition Game	158	19	12%	0.00	31	13	42%	9.2
Xortris	193	59	31%	0.00	67	53	79%	5.9