Algorithms Topic 1 KO

What is an algorithm?

An algorithm is a sequence of ordered instructions that are followed step-by-step to solve a problem. This does not need to be on a computer.

What is decomposition?

Decomposition is the breaking down of a complex problem into
smaller more manageable problems that are easier to solve

What is abstraction?

Abstraction allows us to remove unnecessary detail from a problem
leaving us with only the relevant parts of a problem thereby making
it easier to solve.

What is algorithm efficiency?

More than one algorithm can be used to solve the same problem. Normally we use the algorithm that solves the problem in the quickest time with the fewest operations, or makes use of the least amount of memory.

What are trace tables?

The purpose of the trace tables is for the programmer to track the value of the variables and outputs at each step of the program and to track how they change throughout the running of the program.

Start Stop

Input / Output

Process

Decision

Arithmetic Operators

Add
Multiply
Divide
Subtract
Integer division
Modulus (remainder)

Relational operators

Less than
Greater than
Equal to
Not equal to
Less than or equal to
Greater than or equal
to

Boolean Operators

AND
OR
NOT

If pseudocode

if else pseudocode

if, else if, else pseudocode

What are the three loops in pseudocode?

WHILE
FOR
REPEAT UNTIL