Sphere Online Judge (SPOJ)

list of classical problems

ID	NAME	QUALITY	USERS	ACC %
3900	MinCut Query		78	28.99
3901	Black and White Nim		55	39.23
3922	Mystical River		128	25.67
3926	Manhattan Wire		80	14.07
3927	Polygon on the Grid		23	30.34
3929	Different Digits		74	22.75
3935	SHIFT Operator on Matrix		191	42.38
3939	Search of Concatenated Strings		28	24.40
3941	Kth Shortest Path		25	24.30
3942	Cleaning Robot		34	65.28
3961	Journey with Pigs		133	41.31
3965	Minimax Triangulation		60	40.00
3972	Stargates		49	14.12
3981	Shortest Regular Bracket		82	33.78
4003	Subway planning		43	18.68
4004	Exploding CPU		146	46.49
4008	Con Voi		9	57.69
4010	Chặt cây		11	22.58
4021	Bipalindrome		183	30.77
4034	Pizza Delivery		53	16.51
4052	Game		75	29.27
4060	A game with probability		210	22.15
4062	Rob Mini-Safe		114	39.46
4069	Morphing is Fun		29	16.07
4070	Two Professors		104	14.10
4083	Tele Broadcast		67	50.26
4097	Locomotive		35	37.89
4142	Ellipse		21	9.46
4154	IZBORI		42	26.67
4156	PLAHTE		69	35.77
4160	A1 Road		89	50.90
4172	Multiplicative digital root	1	77	24.16
4178	Distance on a square lattice		130	54.41
4185	Cube		57	35.57
4186	Break a New RSA system	1	138	34.12
4188	Amazing equality		42	13.88
4202	Brackets Parade		238	45.03
4210	Fast Maximum Matching		19	48.08
4211	Fast Maximum Flow		21	24.62
4212	Another Longest Increasing Subsequence Problem		14	42.50
4225	Payment System		31	61.90
4275	rotate it		40	55.70
4278	Battlefield		8	38.89
4307	Stamps		33	41.94
4308	Byteantean towns		58	24.65
4309	Circular game		35	19.60
4311	Quasi-template		62	34.52
4324	The fate of the pineapple		46	28.98
4361	Connected Points		13	34.78
4378	Twofive		66	26.45