Sphere Online Judge (SPOJ)

list of classical problems

ID	NAME	USERS	ACC %	DIFFICULTY C I
7387	Airplane Parking	56	23.90
7389	Rating Hazard	21	16.67
7402	Repair Depots	12	34.78
7409	Drawing Quadrilaterals	51	12.06
7427	Jara’s Legacy	81	39.58
7490	Biology	13	5.79
7556	B - Stock Charts	44	40.32
7558	D - Alphabetomials	11	46.15
7559	E - Football Team	9	17.81
7560	F - Interesting Ranges	11	24.53
7563	Hi6	37	16.95	26 26
7566	Expected Cycle Sums	46	47.66
7579	Power Calculus	312	48.81	34 17
7581	The Best Name for Your Baby	10	31.43
7589	Cave Crisis	13	54.84
7599	Optimal Strategy for the ICPC	9	19.61
7627	Driving Direction	10	59.74
7629	Building Ports	42	12.79
7630	SHOPPERS	149	36.53
7632	Architecture	18	22.92
7666	Telecommunications	23	25.49
7680	Electrical Engineering	15	33.55
7692	Chemistry	69	13.82
7693	Environmental Engineering	38	39.23
7737	Escape	57	34.36
7740	Fence	18	25.35
7745	Bingo!	756	38.84	17 1
7746	Cocircular Points	62	17.12	42 17
7758	Growing Strings	175	32.55
7763	Ingenious Metro	68	66.26
7772	Help a researcher	61	48.68
7777	National Treasure	32	37.00
7779	Stock Chase	73	29.78	17 17
7783	Commuting Functions	46	24.69
7807	The Lucky Prisoner	27	9.84
7857	Tower Game (Hard)	59	15.04	34 34
7862	Prisoner of Benda	24	34.18
7874	Calculator	25	21.71
7884	Crni	57	56.03
7886	Boards (Hard)	35	34.59
7891	Fibonacci Sequence	100	29.38	34 34
7960	Multiplicative Palindrome	30	27.27
7972	World of cubes	34	15.91
8055	Playground	280	25.94
8062	Shopping Rush	73	63.26
8097	Islands	70	46.34
8104	Friendly Knights	151	45.87
8108	POLYU	32	25.71
8189	Circles On A Screen	82	28.04
8282	Distance	51	23.74