December 1999
SE203 : SOFTWARE ENGINEERING

QUESTION 5

Total Marks: 15 Marks

• Question 1
• Question 2
• Question 3
• Question 4
• Cover Page

Click to access
SUGGESTED SOLUTIONS
for Question 5

Consider the following section of simple pseudo-code:

10 PRINT "Hello"
20 PRINT "This is my first program"
30 IF CONDITION C1 IS TRUE,GOTO 50;ELSE GOTO 40
40 END_OF_PROGRAM
50 IF CONDITION C2 IS TRUE,GOTO 20;ELSE GOTO 40

(i)Translate this section of pseudo-code into a flow graph.[2 marks ]

(ii)Based on this flow-graph,derive the value of V (G ).Show all three methods of calculation,with full working.[3 marks ]

(iii)Based on this value of V (G ),derive the basis set of test paths.[2 marks ]

Ensure that you show all steps of working used to derive your answer.

Consider a data variable STATUS that is used to indicate a student ’s status in an examination.There are three possible values for STATUS :

Based on the equivalence partitioning technique,do each of the following for the STATUS data variable:

(i)Identify clearly the invalid class,and valid class of inputs.[2 marks ]

(ii)Present two test cases,one falling into the invalid class,and one falling into the valid class.[2 marks ]

Verification is sometimes thought of as answering the following question:Are we building the product right?Validation activities,on the other hand,are thought of as answering the question:Are we building the right product?
Based on your understanding of verification and validation,

(i)Describe in your own words the difference between these two types of activities. Ensure that the difference is clearly presented in your answer.[2 marks ]

(ii)In your own opinion,explain why it is that end-users (or customers)of the software being developed would be more concerned with the validation activity rather than the verification activity.[2 marks ]