Exam (elaborations)
CAMBRIDGE IGCSE COMPUTER SCIENCE PAPER 2 EXAM Q&A
- Course
- Institution
CAMBRIDGE IGCSE COMPUTER SCIENCE PAPER 2 EXAM Q&A
[Show more]
Content preview
CAMBRIDGE IGCSE COMPUTERSCIENCE PAPER 2 EXAM Q&A
Sequence (flowchart) - Answer-A code construct that flows in order
Selection (flowchart) - Answer-A code construct that makes a choice
Iteration (flowchart) - Answer-A code construct that loops.
Pseudocode - Answer-'Mock' or 'pretend' code - a way of describing an algorithm you
are intending to code without using a specific programming language
ENDIF - Answer-Pseudocode statement that ends an "if" block (we don't need it in
Python but we MUST remember it in pseudocode)
NEXT (counter variable) - Answer-Pseudocode:
A FOR loop must be ended with this
Sequence - Answer-When instructions are executed one after another, e.g.:
INPUT x
y <- x+1
OUTPUT y
Selection - Answer-When a decision is made regarding which instructions get executed
next e.g.
IF mark >= 50
OUTPUT "pass"
ELSE
OUTPUT "fail"
ENDIF
increment - Answer-to make bigger, particularly to make bigger by one
e.g.
i=i+1
or
i += 1
decrement - Answer-to make smaller, particularly to make smaller by one
e.g.
i=i-1
or
i -= 1
, Accumulator Variable - Answer-a variable which we add to eg. as we loop through a list
to compute a total or average
It should usually be initialised to zero before we start adding to it
Iteration (repetition) - Answer-When a block of instructions is executed repeatedly e.g
FOR i = 1 *TO* 10
sum <- sum + i
NEXT i
Self-documenting code - Answer-When code is developed in a way that makes it easy
for another programmer to understand. This can include suitable naming of data
structures and subroutines, and code comments.
All code should be written this way
Type declaration - Answer-When a variable is allocated a particular data type (integer,
string, Boolean, float).
Source Code - Answer-The code written by the programmer before it is translated in to
machine code.
Suitable Naming Conventions - Answer-When subroutines and data structures are
given a name which represents what they do or store.
Indentation - Answer-Positioning a block of code, e.g. a for loop or an if statement,
further from the margin than the main program. The use of indentation makes programs
easier to read.
In Python correct indentation is important, since indenting starts a block and unindenting
ends it.
In Pseudocode it's only important for readibility
Comment - Answer-Text included in code that is for the human reader and is ignored by
the program.
In Python, they are indicated by the # symbol at the start of a line.
In pseudocode they start with //
Subroutine (subprogram) - Answer-A self-contained block of code or small computer
program that runs within another larger computer program.
These split up a program into a number of units, each performing a specific function.
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller biggdreamer. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $15.49. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
81633 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now