Sphere Online Judge (SPOJ)

list of classical problems

ID	NAME	USERS	ACC %	DIFFICULTY C I
1709	Swamp Things	289	40.34
1715	Another Necklace Problem	51	18.18	17 17
1722	Life, the Universe, and Everything II	65	30.46
1725	The Importance	100	38.38	17 17
1726	Exchange	22	7.42	50 34
1739	Yet Another Equation	232	41.18
1772	Find The Determinant II	97	30.56	1 50
1788	Fractan	44	30.16
1793	Text Generater II	54	30.00
1800	Fixed Partition Contest Management	61	36.78
1803	Fold	59	42.86
1810	Nuclear Plants	21	11.51
1815	Problems Collection (Volume X)	77	7.41
1838	Ticket to Ride	88	41.61
1842	Lineland Airport	36	19.49
1865	Making Waves	188	43.49	26 9
1877	Enrich my purse	153	27.01
1880	Hanoi Calls	204	53.99
1962	Circles	61	19.96
1963	Image Projections	106	33.80
1964	Tree cut	148	37.89
1966	Ski Valley	115	18.24
2002	Random Number Generator	98	40.83
2019	The Rolling Ball	3	4.76
2022	Truth Or Lie	104	21.17
2023	One Instruction Computer Simulator	47	10.63	42 42
2031	Please help You-Know-Who	38	28.42
2052	Hexagonal Parcels	75	28.71
2060	Tough Water Level	35	22.13
2070	Minimum Distance	84	16.69	17 1
2129	Cake	71	21.52
2130	Trolls	29	39.19
2132	Puzzle	88	32.46
2140	(un)Fair Play	75	38.22
2141	Golden Garden	17	12.20
2142	Arranging Flowers	24	9.73
2144	K Edge-disjoint Branchings	9	12.46
2147	Root of a Linear Equation	65	8.82	34 17
2151	Digital Calculator	23	5.73
2153	Internet is Faulty	66	37.50
2154	Kruskal	84	13.95
2159	Delicious Cake	29	14.39
2160	Here-There	29	24.76
2161	Pixel Shuffle	33	20.72	50 17
2162	Towers of Powers	26	15.64
2180	Justice League	78	48.06
2202	Tan and His Interesting Game	44	23.00
2270	Balloons in a Box	171	23.69
2271	Undecodable Codes	47	12.08
2272	Crossing the Desert	53	19.88