Pseudo-code, Program Code & Flowcharts Flashcards

All 14 cards in this deck

Which flowchart symbol is a rounded rectangle (oval), and what is it used for?

The terminal symbol — the Start or Stop of the algorithm.

Which flowchart symbol is a plain rectangle, and what is it used for?

The process symbol — a calculation or an assignment to a variable.

Which flowchart symbol is a diamond, and what is it used for?

The decision symbol — a condition with two labelled exits (Yes/No).

Which flowchart symbol is a parallelogram, and what is it used for?

The input/output symbol — data entered into or sent out of the algorithm.

Which flowchart symbol is a rectangle with two extra vertical lines at its sides?

The subroutine symbol — a call to a separate subroutine.

What do the lines with arrowheads in a flowchart show?

The flow of control — the order and direction in which the symbols are followed.

What are the steps to work out the output of a flowchart for a given input?

e.g. input 5 to a flowchart that doubles a number then adds 1

1. Start at the Start terminal and follow the arrows: number = 5
2. Carry out each symbol's instruction, taking the branch that matches at a decision: $5 \times 2 = 10$, then $+1 = 11$
3. Record whatever reaches an output symbol: output 11

What are the steps to complete a missing decision in a partially drawn flowchart?

e.g. an empty diamond whose Yes branch outputs "Pass"; the pass mark is 50

1. Look at what each branch out of the symbol does: Yes gives 'Pass'
2. Work out the condition that must be true to take the Yes branch: score ≥ 50
3. Write it inside the diamond, labelling both exits Yes and No

What are the steps to draw a flowchart for a described algorithm?

e.g. input a number and output "Big" if it is over 100

1. Begin with a Start terminal and a parallelogram for each input: input number
2. Add rectangles for processes and diamonds for decisions with Yes/No exits: number > 100?
3. Add output symbols and a Stop terminal, joining everything with arrows: output "Big"

What are the steps to convert a flowchart decision into AQA pseudo-code?

e.g. a diamond "score > 50?" with Yes → output 'Pass', No → output 'Fail'

1. Write the condition as an IF: IF score > 50 THEN
2. Put the Yes branch underneath: OUTPUT 'Pass'
3. Put the No branch after ELSE, then close: ELSE OUTPUT 'Fail' ENDIF

Name three ways an algorithm can be represented.

Pseudo-code, program code and a flowchart.

What is pseudo-code?

A way of writing out an algorithm in structured, code-like statements without following the rules of any particular programming language.

On a flowchart, how does a sequence differ from selection?

A sequence follows a single path from Start to Stop with no decisions; selection has a decision diamond that splits the flow into different routes.

How does iteration appear on a flowchart?

An arrow leads back to an earlier point, usually from a decision, so a group of steps is repeated.