Matilda Baines GCSE Computer Science Year 11
GCSE COMPUTER
SCIENCE REVISION
Paper 2 – Programming & Logic
0
,Matilda Baines GCSE Computer Science Year 11
Computational Thinking
Algorithms are sets of instructions for solving a problem or completing a task. To solve a
problem, you would use algorithmic thinking to come up with steps to accomplish the task,
some of the ways in which we make it easier to solve the issue include:
Abstraction involves removing unnecessary detail from a problem so that you can focus on
the essential components.
Decomposition involves breaking down a large problem into
smaller sub-problems. This can then be broken down
further to make it more manageable. You can use a
structure diagram to illustrate this dividing of
problems.
Sequence & Selection
Within programming, there are basic program structures such as sequence, selection and
iteration.
Variable = a memory location that stores a value or data and it can change, depending on
conditions or on information passed into the program.
Constant = a memory location that stores a value or data and it cannot change throughout
the program. It will be always equal to this one value.
All programs follow a series of steps to be followed in a sequence. A basic example of this is:
score1 = int(input(“Enter a score for Round 1: ”)) Basically, sequence is just
score2 = int(input(“Enter a score for Round 2: ”)) following the program in a
chronological way, unless there
print(“The average score is” , (score1+score2)/2) are subroutines
Selection is where a section of code will only if a condition is met. Examples of this in
programming are IF statements. A data type that selects is Boolean: something is either
True or False.
if answer == “a” then
print (“Apple”)
elseif answer == “b” then
print (“Banana”)
else
print (“Nope”)
1
, Matilda Baines GCSE Computer Science Year 11
Iteration
Iteration means the repetition of a section of code, with there being three main types
including:
for … next
while … endwhile
do … until
Iteration enables programmers to greatly simplify a program. Instead of writing out the
same lines of code again and again, a programmer can write a section of code once, and ask
the program to execute it again and again until it is no longer needed.
Flowcharts
A flowchart is a diagram that shows an overview of a program. Flowcharts normally use
standard symbols to represent the different types of instructions. These symbols are used to
construct the flowchart and show the step-by-step solution to the problem. Flowcharts are
sometimes known as flow diagrams.
2
GCSE COMPUTER
SCIENCE REVISION
Paper 2 – Programming & Logic
0
,Matilda Baines GCSE Computer Science Year 11
Computational Thinking
Algorithms are sets of instructions for solving a problem or completing a task. To solve a
problem, you would use algorithmic thinking to come up with steps to accomplish the task,
some of the ways in which we make it easier to solve the issue include:
Abstraction involves removing unnecessary detail from a problem so that you can focus on
the essential components.
Decomposition involves breaking down a large problem into
smaller sub-problems. This can then be broken down
further to make it more manageable. You can use a
structure diagram to illustrate this dividing of
problems.
Sequence & Selection
Within programming, there are basic program structures such as sequence, selection and
iteration.
Variable = a memory location that stores a value or data and it can change, depending on
conditions or on information passed into the program.
Constant = a memory location that stores a value or data and it cannot change throughout
the program. It will be always equal to this one value.
All programs follow a series of steps to be followed in a sequence. A basic example of this is:
score1 = int(input(“Enter a score for Round 1: ”)) Basically, sequence is just
score2 = int(input(“Enter a score for Round 2: ”)) following the program in a
chronological way, unless there
print(“The average score is” , (score1+score2)/2) are subroutines
Selection is where a section of code will only if a condition is met. Examples of this in
programming are IF statements. A data type that selects is Boolean: something is either
True or False.
if answer == “a” then
print (“Apple”)
elseif answer == “b” then
print (“Banana”)
else
print (“Nope”)
1
, Matilda Baines GCSE Computer Science Year 11
Iteration
Iteration means the repetition of a section of code, with there being three main types
including:
for … next
while … endwhile
do … until
Iteration enables programmers to greatly simplify a program. Instead of writing out the
same lines of code again and again, a programmer can write a section of code once, and ask
the program to execute it again and again until it is no longer needed.
Flowcharts
A flowchart is a diagram that shows an overview of a program. Flowcharts normally use
standard symbols to represent the different types of instructions. These symbols are used to
construct the flowchart and show the step-by-step solution to the problem. Flowcharts are
sometimes known as flow diagrams.
2
