Sphere Online Judge (SPOJ)

list of classical problems

ID	NAME	QUALITY	USERS	ACC %	DIFFICULTY C I
4275	rotate it		40	55.70
4278	Battlefield		5	44.00
4307	Stamps		27	40.00
4308	Byteantean towns		55	24.22
4309	Circular game		32	19.89
4311	Quasi-template		54	33.92
4324	The fate of the pineapple		40	28.41
4361	Connected Points		9	52.17
4378	Twofive		63	32.26
4407	Counting Arborescence		100	34.02
4409	Circle vs Triangle	1	59	19.77
4410	Repair the Door		58	22.49
4411	Counting Expressions		29	42.47
4412	Factorization, Factorization, Factorization	1	52	41.28
4414	Highway		53	21.89
4420	Counting Graphs		58	34.93
4421	Irreducible polynomials over GF2		62	18.01
4453	Bouncing Balls II		219	27.73
4455	Going to the Movies		86	36.33
4459	Muzidabutur		4	21.43
4461	A Famous Airport Manager		23	16.36
4477	Flower growing		112	22.55
4478	Counting Expressions II		14	35.29
4528	Frog Wrestling		66	43.23
4533	Determinant of Banded Matrices		16	32.67
4551	Match Maker	1	61	22.40
4552	Adding up Triangles		137	36.30
4559	A Day at the Races		122	17.08
4574	Riding in cycles		41	24.31
4585	Star Wars	1	74	35.09
4586	Texas Trip		67	38.25
4588	SETI		125	67.74
4717	Grid Points in a Triangle		97	46.48
4785	Starship		10	28.80
4828	ZSequence		51	19.33
4881	Words on graphs		103	11.39	34
5014	Crazy Receptionist		11	13.18
5015	Decode the Castanets		32	40.19
5016	Guernica		19	51.06
5018	Street Gambler		26	43.55
5093	Pretty Functions	1	39	24.21
5102	Mystic Craft		54	46.05
5103	Top 10		41	16.26
5104	Spam Detection		14	20.69
5115	Two "Ways"		63	14.95
5143	Binary Integer		49	50.85
5144	Cryptography Reloaded (Act I)		33	26.16
5145	Déjà vu		16	19.23
5146	Experiment on a … Cable		12	41.38
5149	History of Languages		27	15.54