Sphere Online Judge (SPOJ)

list of classical problems

ID	NAME	USERS	ACC %	DIFFICULTY C I
9944	Ji-Tu Problem	14	12.50
9950	IQ Team	37	41.59	50 50
9968	Magic Crystals and Laser Beams	179	23.48
9970	The Egyptian Parliament	49	18.84
9971	Adventurous Chess Masters	19	22.32
9974	Men From Mars	22	39.66
10071	Working at the Restaurant	32	37.78
10074	Genetics	9	33.33
10076	Slalom	30	34.44
10077	Routing	15	38.64
10081	Periodic Points	12	40.00
10082	Comparing Answers	57	12.59
10084	Fake Scoreboard	23	45.21
10086	Jumping Monkey	54	24.87
10087	Sensor Network	23	21.85
10088	Assembly Line	34	40.43
10091	Three-sided Dice	27	20.71
10092	Party Night	28	41.89
10095	Caper Pizza	27	27.56
10096	Lights (Extreme)	55	30.25	17 17
10105	Alphabet Soup	28	50.00
10106	Coin Collecting	42	39.64
10109	Game, Set and Match	94	66.86
10110	Guess the Numbers	123	44.21	17 17
10112	Peer Review	116	32.71
10113	Regular Convex Polygon	95	29.50
10141	STRAZA	45	46.51	34 17
10230	Robbing Gringotts	53	10.96
10242	Dice on a Board	17	30.00
10265	Subdivision of the kingdom	33	33.55
10377	project groups	128	50.69	34 34
10419	Polish Language	96	25.09
10421	Run, Snipe, Run	73	30.00
10425	Security System	25	54.24
10437	Quadrilaterals	73	30.28
10439	Walking Robot	110	46.11	34 34
10440	Friends	32	20.25
10443	Bridges	1	7.14
10444	Coding	97	35.58
10447	Contaminated City	69	13.63
10449	Resource Management	15	25.96
10450	Amoeba	98	17.32
10451	Stun Boosting	17	27.38
10454	Greens Land	96	28.21
10461	The magical escape	32	53.33
10465	One Theorem, One Year	46	42.86
10476	Fair bases	37	35.71
10506	Prendonians	50	29.35
10507	Cheese-rolling World Cup	53	33.51
10508	Buttons	45	24.77