Aims & Achievements

I can create a comprehensive test plan for a given program with normal, extreme and exceptional data sets along with expected results. 

I can identify syntax, execution and logic errors in a program design.  

I can conduct a dry run with the use of a trace table to map the expected values of variables while a program is running. 

I can describe how breakpoints and watchpoints can be used to aid in debugging a program. 

Achievements

We are learning how to develop a set of test data to comprehensively test a program. 

We are leaning how to identify syntax, execution and logic errors in program code. 

We are learning how to use new debugging techniques. Specifically:

dry runs  

trace tables/tools  

breakpoints 

watchpoints 

Aims

​Past paper question

A mathematician has written a program to generate the first six numbers in a mathematical sequence. The next number in the sequence is the sum of the previous two numbers. For example, if the sequence starts with 5,7, . . . Then the first six numbers of the sequence would be 5, 7, 12, 19, 31, 50  

The following code has been developed to generate the sequence of six numbers. 

A logic error in the code means that an incorrect sequence is generated. The trace table below shows the line numbers where a variable has changed. 

​Past paper question

A logic error in the code means that an incorrect sequence is generated. The trace table below shows the line numbers where a variable has changed. 

State the missing values at A, B and C. (3 marks) 

​Past paper question - Solution

A= [5,7,0,0,0,0]
B= [5,7,7,0,0,0]
C= [5,7,7,7,0,0]

1 mark per line