2.In a B+ tree, leaves and nonleaf nodes have some key values in common.
T
F
3.A 2-3 tree with 12 leaves may have at most 10 nonleaf nodes.
T
F
选择题
1.Among the following statements, which one does NOT satisfy the definition of a B tree of order m?
选项
A
All the leaf nodes are linked by pointers
B
The root has at most m subtrees
C
All the leaf nodes are on the same level
D
Inside each node, the keys are arranged in sorted order
2.B+树不同于B树的特点之一是：
选项
A
能支持顺序查找
B
结点中含有关键字
C
根结点至少有两个分支
D
所有叶结点都在同一层上
3.After deleting 9 from the 2-3 tree given in the figure, which one of the following statements is FALSE?
选项
A
the root is full
B
the second key stored in the root is 6
C
6 and 8 are in the same node
D
6 and 5 are in the same node
4.Which of the following statements concerning a B+ tree of order M is TRUE?
选项
A
the root always has between 2 and M children
B
not all leaves are at the same depth
C
leaves and nonleaf nodes have some key values in common
D
all nonleaf nodes have between ⌈M/2⌉ and M children
5.A B+ tree of order 3 with 21 numbers has at most __ nodes of degree 3.
选项
A
1
B
2
C
3
D
4
6.一棵有21个数字的、度为3的B+树最少有 __ 个度为2的结点。
选项
A
0
B
1
C
2
D
3
7.Which one of the following is NOT true about B+ trees and AVL trees: they are both __。
选项
A
balanced binary trees
B
fit for sequential searches
C
fit for random searches
D
fit for range searches
8.Given a 2-3 tree as shown in the figure, after inserting 7 with splitting strategy, what is (are) the key(s) in the root?
选项
A
4
B
6
C
8
D
4 and 6
9.Given a 2-3 tree as shown in the figure, after inserting 18 with splitting strategy, where will the key 15 be?
选项
A
in the root alone
B
in the root with key 20
C
alone in a node on the second level (the leaves are on the first level)
D
in a node with key 11 on the second level (the leaves are on the first level)
10.The minimum number of keys in a B tree with order 3 and height 5 is __.
选项
A
15
B
31
C
62
D
242
11.After inserting 0 into the 2-3 tree given in the figure, how many of the following statements are FALSE?
(S1) The tree grows higher;
(S2) 2 and 4 are in the same interior node;
(S3) the root node still contains 9 only;
(S4) the interior node containing 12 keeps unchanged.
