Sphere Online Judge (SPOJ)

list of classical problems

ID	NAME	USERS	ACC %	DIFFICULTY C I
20863	Largest Submatrix	80	26.92
20951	Pebbles	18	49.02
20971	Alia and Substrings	20	21.99
20980	Chicken Joggers	14	55.88
21058	Dirty Plates	23	44.44
21135	Distinct Viewpoints	2	50.00	34 1
21155	Manoj and Fire	20	25.38
21171	Fractal domino	14	50.88
21173	String fertilization	58	45.23
21175	Rush hour	141	41.77
21176	Stapled intervals	49	60.67
21178	Encryption kit	49	31.15
21352	Avantgarde and Bicycle	22	37.84
21407	2x2 Subgrid Sum Problem (medium)	17	21.24
21463	Arithmetic Rectangle	34	21.27
21585	Hazzat’s Query	70	25.76
21962	GREAT SWERC	20	57.50
21967	City Park	17	44.23
21968	Playing with Geometry	15	66.67	17 1
21969	Money Transfers	4	26.32
21970	Safe Secret	18	42.00
22002	English	17	17.09
22090	Prime Power Test (Hard)	11	21.80	50 50
22271	Periodic function, trip 3	10	57.78	34 17
22315	Periodic function, trip 3 (easy)	11	27.45	17 17
22320	Polynomial Drawing	2	15.38
22530	Tinku got a job	16	16.67
22552	Flow on Tree	41	47.12
23134	Help Me Please!	25	23.62	1 17
23350	Mineral Farm	16	24.17	34 34
23351	Hiccup And Lucky Dragons	15	9.79	26 17
23383	ISOMORPH	28	43.65
23435	Game Calculator	1	7.69
23877	The Long Pile Game	28	23.64	17 17
23882	Watchers On The Wall	28	22.46
25214	Ohani And The Game	77	20.19	11 8
25336	Eefun Plays Doto	4	31.03
25382	Meetings	13	31.51
25452	Teaching Hazard	7	50.00
25480	Invading aliens	14	16.39
25684	Jolly Kingdom	17	16.51
25818	NEKAMELEONI	12	14.38
25960	Cat and Mouse I	55	14.32
26181	Walking Jumper	5	28.57
26187	Captain Claw	59	25.16	17 12
26306	Pointers	23	32.95
26695	Atul and Aastha Chronicles 2	137	36.67	11 9
26744	Coverage	21	38.20
26843	Who is the Best?	4	31.58
27092	Balanced Diet	14	39.53