Sphere Online Judge (SPOJ)

list of classical problems

ID	NAME	USERS	ACC %	DIFFICULTY C I
272	Cave Exploration	38	9.84	17 1
275	The Water Ringroad	2	10.81
278	Bicycle	55	13.03	34 1
280	Lifts	42	17.23	17 1
283	Naptime	575	24.81	17 1
290	Polynomial Equations	61	22.79	17 17
293	Officers on the Beat	11	21.43
296	Teamwork is Crucial	68	31.29
318	Pythagorean Legacy	27	22.22	1 34
325	The Tall Windmills	82	24.75	34
327	Platon and Socrates	49	12.64	9 34
332	Hard Question	100	30.63	1 34
334	The Philosophical Dispute	55	40.48	17 17
351	Ha-noi!	381	42.26	1 1
369	Math I	86	25.35	34 34
371	Boxes	528	35.60	1 26
374	Count maximum matrices	234	20.82	1 17
380	Bullshit Bingo	707	33.43
382	Decorate the wall	213	35.24	1 17
383	European railroad tracks	222	30.23
385	Game schedule required	148	28.71	34 1
386	Help the problem setter	97	45.82
391	Railroads	84	17.74	17 17
392	Spin	37	24.39	1 17
393	Hexagon	69	48.68	17 1
396	Hit or Miss	129	45.03	1 1
398	Roll Playing Games	117	14.15	34 17
401	Translations	131	38.11	17 34
404	Scanner	56	12.24
405	Tin Cutter	134	33.72	17 17
406	Logic	107	22.51	17 9
407	Random Number	43	27.93	17 17
412	K-path cover	181	20.04	1 50
418	Necklace	43	16.76
421	Another Road Problem	67	24.36	17 34
481	Roots of polynomial	37	24.90	17 34
484	Fossil in the Ice	434	22.10	34 17
598	Increasing Subsequences	141	33.90
677	A place for the brewery	209	27.63
682	Pairs of Integers	203	25.59
697	Matrix Words	94	26.20
700	Branch Prediction	74	18.00
702	Barn Expansion	151	23.30
729	Move your armies	77	20.04
734	Ivan and his interesting game	228	34.19
757	Thermal Luminescence	121	39.26
760	Convex Hull 3D	117	41.56
780	The Archipelago	36	42.18	45 34
827	Trigonometric optimization	77	27.87
850	Soccer Choreography	4	4.02