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What is the first stage of the program development life cycle?
Analysis
What tools are used in the analysis stage? Abstraction and decomposition tools
What is the purpose of the design stage? To develop the design of the program using structure charts, flowcharts, and pseudocode.
What is the next stage after the design stage? Coding
What is done in the testing stage? The completed program is run many times with different test data to ensure all tasks work together as specified.
How many stages is the program development life cycle divided into?
Five
Name the five stages of the program development life cycle.
Analysis, Design, Coding, Testing, and Maintenance
What are the components of a computer system? Software, data, hardware, communications, and people.
How can a computer system be divided? Into a set of sub-systems.
What is the characteristic of each sub-system in a computer system?
It can be further divided into sub-systems until each sub-system performs a single action.
What is decomposition in the context of a computer system?
The process of breaking a computer system into sub-systems, then breaking each sub-system into smaller sub-systems, until each sub-system performs a single task.
Why is decomposition important in problem-solving using a computer system?
To break down the problem into its component parts for effective solution.
What are the inputs in the context of a computer system?
The data used by the system that needs to be entered while the system is active.
What are the processes in the context of a computer system?
The tasks that need to be performed using the input data and any other stored data.
What are the outputs in the context of a computer system?
Information that needs to be displayed for the user of the system.
What is storage in the context of a computer system?
Data that needs to be stored in a file for future use.
What does breaking a problem down into smaller parts/tasks make it easier to do?
Understand, solve, and manage.
What does top-down design allow several programmers or teams to do?
Work on the same project/task without interference.
How should each sub-system of code be tested in top-down design?
Separately.
What does abstraction do? Keeps key elements required for the solution and discards unnecessary details.
What type of diagram can be used to show top-down design in a diagrammatic form?
Structure Diagram
What does a Structure Diagram show in a hierarchical way?
The design of a computer system
What is an algorithm? A procedure used for solving a problem or performing a computation.
How can an algorithm be represented? Through flow charts and pseudocode.
What is pseudocode? A method of expressing an algorithm design using English key words similar to those in a high-level programming language.
What does pseudocode describe? What the algorithm does.
Are there definitive rules for writing pseudocode? No definitive rules, but it should make sense and logically solve the problem/task.
What is the purpose of pseudocode? To logically solve a problem/task before coding it into an actual programming language.
What is the statement used for the display of information/result to the user?
OUTPUT/ PRINT
What are the three basic programming constructs? Sequence, selection, and repetition.
What does sequence indicate in coding? The order in which the code is written, usually from top to bottom.
What is a selection in programming? A construct used to determine a different set of steps to execute based on a decision or condition.
How does a selection affect the code execution? It causes the code to branch and follow a different sequence based on the decision made by the program.
What happens if the condition in an IF statement is true?
The THEN path is followed.
What happens if the condition in an IF statement is false?
The ELSE path is followed if it exists, otherwise the statement moves to the next instruction after ENDIF.
What indicates the end of an IF statement? ENDIF.
What are the two ways to set up a condition? Using a Boolean variable or using comparison operators.
What are the possible values of a Boolean variable? TRUE or FALSE.
What is the purpose of comparison operators in setting up a condition?
To compare values and make decisions based on the comparison.
What does the '>' operator signify in setting up a condition?
Greater than.
What does the '<' operator signify in setting up a condition?
Less than.
What does the '=' operator signify in setting up a condition?
Equal.
What does the '>=' operator signify in setting up a condition?
Greater than or equal.
What does the '<=' operator signify in setting up a condition?
Less than or equal.
What does the '<>' operator signify in setting up a condition?
Not equal.
What is the purpose of the CASE...OF statement? To test the value of a variable and compare it with multiple values.
What happens when a case match is found in a CASE...OF statement?
A block of statements associated with the matching case is executed.
What happens if a case match is not found in a CASE...OF statement?
The OTHERWISE statement is executed.
What is the term for repeating actions as part of an algorithm?
Iteration
What are the three different types of loop structures in pseudocode?
- FOR ... TO ... NEXT (Count Control Loop), 2. WHILE ... DO ... ENDWHILE (Conditional Control Loop), 3. REPEAT ... UNTIL (Conditional Control Loop)
What is the purpose of a for loop? To iterate a specific number of times.
How is a variable used in a for loop? It is set up with a start value, an end value, and an increment.
What is the structure of a for loop in some programming languages?
FOR ... TO ... NEXT.
When is the WHILE...DO...ENDWHILE loop used? When the number of repetitions/iterations is not known and the actions are only repeated WHILE a given condition is true.
What happens if the WHILE condition is untrue when the loop is first entered?
The actions in the loop are never performed.
