Sphere Online Judge (SPOJ)

list of classical problems

ID	NAME	USERS	ACC %	DIFFICULTY C I
1842	Lineland Airport	37	18.64
1877	Enrich my purse	153	27.01
1880	Hanoi Calls	205	54.44
1962	Circles	62	20.12
1963	Image Projections	109	34.26
1964	Tree cut	149	38.10
1966	Ski Valley	117	18.43
2002	Random Number Generator	98	40.62
2019	The Rolling Ball	4	5.48
2022	Truth Or Lie	104	21.17
2023	One Instruction Computer Simulator	47	10.58	42 42
2031	Please help You-Know-Who	39	28.65
2052	Hexagonal Parcels	76	28.93
2060	Tough Water Level	36	18.21
2070	Minimum Distance	86	16.85	17 1
2129	Cake	70	21.59
2130	Trolls	29	39.19
2132	Puzzle	89	32.68
2140	(un)Fair Play	75	38.08
2141	Golden Garden	17	12.20
2142	Arranging Flowers	25	9.87
2144	K Edge-disjoint Branchings	9	12.35
2147	Root of a Linear Equation	66	8.90	34 17
2151	Digital Calculator	23	5.69
2153	Internet is Faulty	69	38.54
2154	Kruskal	85	14.03
2159	Delicious Cake	30	14.64
2160	Here-There	30	24.76
2161	Pixel Shuffle	34	21.03	50 17
2162	Towers of Powers	26	13.87
2180	Justice League	83	48.97
2202	Tan and His Interesting Game	46	25.18
2270	Balloons in a Box	172	23.77
2271	Undecodable Codes	48	12.27
2272	Crossing the Desert	54	20.12
2273	Ferries	32	18.75
2275	Toil for Oil	15	28.65
2318	Overlapping Words	90	22.40
2319	Sequence	218	28.12
2323	Broken Compass	47	13.78
2325	String Distance	214	21.51
2413	Building Beacons	42	19.84
2417	Eliminate The Enemies	22	19.74
2418	Flying Frogs	63	35.71
2420	Hospital at Hands	31	23.44	34 34
2423	Minimal Triangulations of Graphs	31	35.09
2485	Phone Lines	19	14.19
2511	Magic Program IV	27	17.99
2631	Chomp	111	45.70
2643	Starcraft I	58	22.30