Computer Science for IGCSE & O level - Algorithm Design And Problem Solving (Section 8)
1
What does the 'range check' validation check in the provided material accomplish?
Answer(B)
It checks if the entered value is within a specified interval.
2
In a flowchart, which symbol represents the beginning or end of a program?
3
Which elements are commonly found within a trace table?
4
What is the primary function of the 'IF-THEN-ELSE' construct in programming?
Answer(B)
To handle different code paths based on a condition.
5
What is the primary purpose of a presence check?
Answer(B)
To verify that a user has entered data into a required field.
6
Which data validation methods assist in the verification process?
7
What kind of check is exemplified by the prompt 'Please enter the student's mark'?
8
Which of the following is the most efficient approach to reading values from a file?
Answer(A)
Using the FOR...TO...NEXT loop with an array.
9
What is a 'flag' variable used for in an algorithm?
Answer(B)
To indicate the status of a condition.
10
What types of things can be done with a CASE OF - OTHERWISE - ENDCASE conditional statement?
Answer(A)
Choose between many different values
11
Which is the usual series of steps used to calculate a check digit?
Answer(B)
Multiplying, adding, and dividing.
12
In the context of data validation, what is the central role of a check digit?
Answer(B)
To find errors, particularly those that may happen during data entry.
13
What happens when the `Found` flag variable is set to TRUE in the linear search example?
Answer(B)
The algorithm immediately stops and indicates that the item has been found.
14
Which data validation method is used to verify that a user has entered their email address in a valid format?
15
What does the term 'sub-system' refer to in the context of computer systems?
Answer(C)
A self-contained component within a larger system.
16
What is the purpose of the coding phase in the program development process?
Answer(B)
To write the program code based on the design.
17
In the linear search algorithm example, how is a match indicated?
Answer(A)
The variable 'Found' is set to TRUE.
18
What is the principal advantage of a screen/visual check in data validation?
Answer(B)
It allows the user to verify the correctness of the data before it's processed.
19
When designing an algorithm, what is the role of 'verification'?
Answer(A)
To compare the algorithm's results with expected outputs.
20
What type of test data is used to find the largest and smallest number?
21
What does the term 'module' refer to within an algorithm?
Answer(A)
A section of code designed to perform a specific task.
22
In algorithm analysis, trace tables are most useful for?
Answer(B)
Understanding how variable values change over time.
23
In pseudocode, `FOR Index <- 1 TO 10 DO` represents which fundamental programming concept?
24
What does the term 'iteration' mean in the context of algorithms?
Answer(B)
The process of repeating a set of actions.
25
What does a trace table primarily help you understand about an algorithm?
Answer(C)
How its variables change as it runs.
26
In the bubble sort algorithm, what causes a swap of two numbers?
Answer(D)
The values are in the incorrect order.
27
In the context of program development, what does abstraction primarily involve?
Answer(B)
Focusing on the essential details while hiding unnecessary ones.
28
In a flowchart, what is the most appropriate symbol to indicate an action to be performed?
29
A double entry check is used to:
Answer(B)
Compare the input of two different operators.
30
Which statement type allows for different actions based on a condition?
31
What is the main advantage of using a REPEAT...UNTIL loop when compared to a WHILE...DO...ENDWHILE loop?
Answer(A)
The REPEAT...UNTIL loop always runs at least once.
32
What is the objective of 'counting' in algorithms?
Answer(C)
To determine the number of occurrences of a specific event or condition.
33
What is the main purpose of writing and amending algorithms?
Answer(C)
To make the program correct, efficient, and maintainable.
34
In the context of data validation, what is a 'presence check' designed to verify?
Answer(A)
If a data value is present in the dataset.
35
What is the primary goal of a screen/visual check during data validation?
Answer(B)
To give the user a final chance to confirm that the entered data is correct.
36
In a `CASE OF` structure, what determines which case's code is executed?
Answer(C)
The value of a control variable.
37
Which of the following operators has the highest precedence?
38
What type of data is most suitable for determining the largest and smallest acceptable values in an algorithm?
39
What is the key feature of the `REPEAT...UNTIL` loop structure?
Answer(B)
The loop always runs at least once.
40
What is an essential part of a check digit's use?
Answer(B)
Multiply, add, and divide.
41
What does 'decomposition' mean in the context of problem-solving?
Answer(B)
Breaking a complex problem into smaller, simpler parts.
42
Which of the following are key elements of program development life cycle (from the image)?
43
Which of the following describes the functionality of a terminator symbol in a flowchart?
Answer(B)
Indicates the start or end of the flowchart.
44
The procedure for check digits often involves these operations:
Answer(C)
Multiplying, adding, and dividing.
45
Which of the following best describes what "abnormal data" is used for?
46
A type check is designed to validate?
Answer(B)
The type of the variable.
47
In algorithm design, what is the purpose of ‘abnormal data’?
Answer(A)
To check how the algorithm functions when the data is out of boundaries.
48
Which type of data validation ensures that the format of the data entered adheres to a specific pattern?
49
What is the best definition of "normal data" in the context of program testing?
Answer(C)
Data that is within the expected range and should produce the intended result.
50
Trace tables are used to document the ____ of an algorithm.
