Sphere Online Judge (SPOJ)

list of classical problems

ID	NAME	QUALITY	USERS	ACC %	DIFFICULTY C I
2129	Cake		70	21.63
2130	Trolls		29	46.03
2132	Puzzle		85	32.11
2140	(un)Fair Play		74	38.68
2141	Golden Garden		17	17.70
2142	Arranging Flowers		23	9.57
2144	K Edge-disjoint Branchings		9	16.14
2151	Digital Calculator		22	5.81
2153	Internet is Faulty		64	41.34
2154	Kruskal		83	14.81
2159	Delicious Cake		29	16.00
2160	Here-There		27	26.63
2162	Towers of Powers		28	19.72
2171	Ambiguous Codes	1	80	38.22
2177	Galou is back!	-1	223	31.13
2180	Justice League		76	48.04
2185	Musical Optimization	1	69	42.36
2202	Tan and His Interesting Game		42	23.76
2270	Balloons in a Box		164	23.46
2271	Undecodable Codes		46	13.01
2272	Crossing the Desert		50	19.18
2273	Ferries		28	17.39
2275	Toil for Oil		13	30.72
2318	Overlapping Words		88	22.70
2319	Sequence		216	28.03
2323	Broken Compass		41	13.42
2325	String Distance		210	21.18
2413	Building Beacons		40	32.58
2417	Eliminate The Enemies		22	26.79
2418	Flying Frogs		57	37.43
2419	G-Line Grid	1	4	7.14
2423	Minimal Triangulations of Graphs		27	33.33
2485	Phone Lines		18	17.80
2511	Magic Program IV		27	17.99
2631	Chomp		110	45.67
2643	Starcraft I		54	22.25
2658	Art of War		17	17.65
2661	Illumination		6	3.40
2662	Put a Point in a Hyperspace		17	11.06
2709	Untitled Problem		27	17.75
2733	K Equal Digits		10	11.96
2734	Large party		34	24.35
2855	Forest		57	12.20
2877	Another understanding of Super Dice Game		64	10.00
2879	The Cow Doctor		141	37.24	17
2898	Party of Cloaked Killers		29	21.15
2903	Transportation		11	46.43
2940	Untitled Problem II		116	15.16	34
2944	Emmons		7	8.28
2962	Painting Blocks (Act I)		107	58.24