CSCI 203 Data Structures Fall 2012 Exam #2

Instructions: The usual…this test is closed book, closed notes, closed computer/phone, closed neighbor, but hopefully open mind.  Write your answers in the space provided.  If you need more space, move to the back of one of the pages and indicate where I can find your answer.  Write legibly—if I can’t read it, it’s wrong.  Read through the entire test before answering any questions in order to find the easy questions and answer them first to maximize your score.  Each question is worth 5 points.  Good luck and have fun!

 

I.      TREES

A.    We can store binary trees in arrays.  Draw the binary tree represented by the array shown below.

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

index

d

r

w

g

-

m

k

a

e

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-

-

s

y

s

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-

b

v

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-

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j

p

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C

z

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B.    What are the three types of nodes that make up a tree?

 

 

 

 

 

 

 

 

 

 

C.    What is the difference between a complete and a full binary tree?

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

D.    The following binary tree is being used to store a general tree.  Draw the general tree it stores.

 

 

 

 

 

 

 

 

 

 

 

E.    If we start counting levels with 0, how many nodes are on level 7? 

 

 

 

 

 

 

 

 

 

 

F.    How many nodes are in a full binary tree with 7 levels?

 

 

 

 

 

 

 

 

 

 

 

G.    The following numbers are inserted into a binary search tree in the order given.  Draw the resulting binary search tree.

10, 15, 13, 14, 20, 1, 4, 6, 2, 5, 8

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

H.    Convert the following tree into a heap.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

I.      For the graph in question H, list the order the nodes are processed for a postorder traversal.

 

 

 

 

J.     For the graph in question H, list the order the nodes are processed for a level order traversal.

 

 

 

 

II.     GRAPHS

K.    How many edges are there in a minimal spanning tree for a connected graph with n nodes?

 

 

 

 

 

 

 

 

 

 

L.     What properties must a graph have for Dijkstra’s shortest path all points algorithm to work?

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

M.   For the graph above, find a minimal spanning tree.

 

 

 

 

 

 

 

 

 

 

 

 

 

N.    For the graph above, find the shortest path all points using Dijkstra’s algorithm.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

III.    SORTING

O.    Name two sorts that have computational complexity O(n2).

 

 

 

 

 

P.    Name two sorts that have computational complexity O(n log(n)).

 

 

 

 

 

Q.    What is the term for a sort that preserves the initial order of two items of equal value?  (In other words, if there are two 10’s in the list, after the list is sorted, the 10 that came first in the unsorted list comes first in the sorted list.)

 

 

 

 

 

R.    Given the array of numbers shown below, show the results of each pass of the insertion sort in the following rows.

 

Original array

1

8

5

7

12

3

9

Pass 1

 

 

 

 

 

 

 

Pass 2

 

 

 

 

 

 

 

Pass 3

 

 

 

 

 

 

 

Pass 4

 

 

 

 

 

 

 

Pass 5

 

 

 

 

 

 

 

Pass 6

 

 

 

 

 

 

 

Pass 7

 

 

 

 

 

 

 

 

 

 

 

 

 

 

S.    Briefly describe the Shell sort algorithm.

 

 

 

 

 

 

 

 

 

 

 

 

T.     If you have a collection of student records that you want to be sorted by classification (freshman, sophomore, etc), and within classification, by last name, and then within last name by first name, in what order do you sort the three fields (classification, last name, first name)?

 

 

 

 


IV.   BONUS(5 points—49 empty squares)

8

 

 

 

6

 

2

7

 

 

 

7

8

 

 

 

4

9

 

 

 

 

5

7

6

 

8

 

 

5

7

 

8

 

 

 

4

 

 

 

 

 

 

 

7

 

 

 

2

 

1

4

 

 

2

 

9

5

8

 

 

 

 

5

6

 

 

 

3

7

 

 

 

3

4

 

7

 

 

 

2