Sphere Online Judge (SPOJ)

ID	NAME	QUALITY	USERS	DIFFICULTY C I
30785	Ada and Apple	11	96	31 26
32952	Ada and Football	2	45	50 42
32223	Ada and Lychees	3	9	42 26
28449	Ada and List	8	245	13 19
32856	Ada and Contact	1	17
30760	Ada and Travelling Salesman	15	140	24 30
15454	How to Handle the Fans	34	1352	11 11
5832	AND Rounds	48	1571	17 20
27379	Unique Code	19	98	20 20
61	Brackets	167	4500	18 20
14742	Building Bridges(HARD)	10	360	14 17
6168	Building Bridges	25	1455	11 16
23742	Dolan and Nephews	4	42	30 27
33019	Catering Contracts	6	76	22 26
12563	Halt The War	6	317	20 19
13015	Counting Primes	29	947	15 14
7296	Trees Again	4	155	21 30
9722	Insertion Sort	23	3052	12 12
5296	Air Combat		54
10628	Count on a tree	53	1494	32 32
10707	Count on a tree II	48	1194	32 33
11414	Combat on a tree	3	118	30 34
11482	Count on a trie		37	34 50
16245	Living with Courage	18	518	9 14
1108	Card Trick	58	1878	22 24
10810	Its a Murder!	50	2061	16 17
3978	Distance Query	45	1046	22 20
3267	D-query	377	7782	19 23
9577	Dynamic Tree Connectivity	10	340	30 25
1684	Frequent values	105	3066	20 20
18185	Give Away	19	380	22 20
11985	Gao on a tree	18	404	29 26
12005	Grass Planting	6	228	37 17
1043	Can you answer these queries I	532	10020	25 24
1557	Can you answer these queries II	20	939	30 35
1716	Can you answer these queries III	203	7298	22 21
2713	Can you answer these queries IV	57	1852	21 21
2916	Can you answer these queries V	44	1692	22 23
4487	Can you answer these queries VI	21	854	34 30
6779	Can you answer these queries VII	12	491	39 25
19543	Can you answer these queries VIII	8	91	36 38
132	Help R2-D2!	12	715	22 18
12210	High and Low		61
8002	Horrible Queries	363	9102	19 18
18247	Arrangement Validity	10	178	17 23
18248	Maggu’s Solar Panels	1	39	34 34
26721	I LOVE Kd-TREES III	3	64	34 34
37375	Kingdom of Equality	2	5	34 34
3693	Maximum Sum	52	5559	20 18
8985	Line up	16	331	17 18

#tree

Tree is a data structure that simulates a hierarchical tree structure

https://en.wikipedia.org/wiki/Tree_(data_structure) https://en.wikibooks.org/wiki/Data_Structures/Trees http://www.i-programmer.info/babbages-bag/477-trees.html