Algorithms - Computer Science

Algorithms

An algorithm is a sequence of clear instructions that are used to solve a problem step by step.

Decomposition

Decomposition is about breaking down a problem into smaller problems that are easier to manage.

Abstraction

Abstraction is the process of making a complex problem easier to understand by focusing only on necessary information.

Pattern recognition

Pattern recognition involves following the process of abstraction and decomposition to try to identify patterns that will help to solve problems.

start/stop flowchart symbol

The terminator must always include the word START at the beginning and STOP or END at the end. The only exception is a loop that continues forever which does not need a STOP terminator.

process flowchart symbol

Process used to represent a process that needs to be carried out in the algorithm, such as an instruction.

Input or Output flowchart symbol

Input or Output representing data that is needed as an input to the algorithm or data that is output from the algorithm.

Subprogram flowchart symbol

Subprogram or subtask that is called to run

arrow flowchart symbol

Connects the symbols showing the direction of flow through the flowchart.

Decisions

A question can be asked which will require a response. The response will determine which direction to take next in the flowchart.

Selection

Selection algorithms require a decision to be made and include the decision symbol. Each option must lead to another part of the flowchart.

Iteration

Iterative algorithms also require a decision to be made but the outcome of the decision will enable processes to repeat.