Sphere Online Judge (SPOJ)

list of classical problems

ID	NAME	QUALITY	USERS	ACC %	DIFFICULTY C I
30945	Non Coprime Sequences	2	20	21.08	50 50
31971	NEO	1	10	3.60	34 50
31975	Ada and Scarecrow		14	16.86	50 50
32028	Ada and Parties		3	1.38	50 50
33039	Amazing Factor Sequence (hard)	2	17	61.42	50 50
33048	Find Linear Recurrence	4	23	34.48	42 50
33062	LCM Pesticide	1	6	30.00	50 50
35675	Primes in GCD Table (Hard)	2	9	30.77	50 50
36789	Linear Diophantine Equation	2	7	15.93	50 50
37446	Breaking Math	2	7	26.15	50 50
40501	A Simple Sieve	3	5	16.67	45 50
16063	Hackers	6	57	23.48	48 48
18932	Sum of primes (reverse mode)	5	21	17.44	45 45
60	The Gordian Dance	3	206	39.08	12 45
1797	Cardsharper	2	7	29.73	34 45
14122	Inverse of Recurrence Problem With a Square Root	3	59	49.56	23 45
15250	Swap (Hard - Level 1000)	3	6	29.11	34 45
19975	Amazing Prime Sequence (hard)	5	80	41.73	39 45
34112	The Sum of Unitary Divisors	1	57	32.20	17 45
37422	Recurrence Power Sum	3	24	19.79	42 45
34096	Counting Divisors (general)	4	305	34.65	40 43
105	Alice and Bob	3	165	27.12	42 42
145	Aliens	2	419	29.78	34 42
687	Repeats	1	864	25.29	34 42
1453	Optimal Connected Subset		148	45.94	26 42
1553	Backup Files	3	753	19.44	9 42
2023	One Instruction Computer Simulator		41	11.22	42 42
2189	Making Pairs	1	44	16.21	34 42
2322	Tree Game	2	323	44.01	26 42
2961	Triomino Game	2	236	28.36	26 42
3833	Tresnja	1	126	52.36	42 42
3896	Maximal Independent Set	2	58	25.20	34 42
4063	Sell Pigs	2	386	48.95	26 42
4157	Domino	4	54	50.42	42 42
6044	Minimum Diameter Circle	1	432	27.29	34 42
8075	Sequence	2	47	27.60	42 42
8991	Number Guessing Game 2	3	130	36.76	17 42
9888	Bird tree	1	296	65.12	34 42
10107	Cybercrime Donut Investigation	2	54	26.94	34 42
10376	String Factorization!	1	43	10.98	26 42
11851	Power with Combinatorics(HARD)	1	127	13.10	34 42
12352	HNumbers	2	200	27.38	23 42
15257	Partition function (HARD)	1	6	2.93	50 42
15556	Count right angle triangles	3	44	24.35	34 42
19913	Counting Pythagorean Triples	3	16	14.23	26 42
32952	Ada and Football	2	196	38.39	50 42
34863	A Cumulative Sum Problem	5	27	20.77	34 42
35631	Moon Safari (Extreme)	2	9	20.94	42 42
36668	Not So Blind Escape	2	7	31.94	34 42
36946	March Of The King	2	13	37.50	42 42

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