Thursday 10 January 2013

IPO, Pseudocode, Flowchart

IPO chart

IPO chart is graphical representation of the input, processing and output steps of a problem. It is the second step in computer-based problem solving (i.e. Analyse the problem).

Scenario1. One is ask to create a program to calculate area.
Now look a simple problem!!! Creating psuedocode can be made easier by writing an IPO chart as followed.
Input
Processing
Output
Length
Width
Accept two numbers store in length and width
Area
Multiply length by width and store in area
Display area
As showing above columns as filled with the appropriate information.

Psuedocode

Pseudocode is a algorithm using instructions with words and symbols that closely resemble computer programming language instructions. The word pseudo means fake. The word pseudocode mean fake-code. Psuedocode are used without following the rigid rules of a computer programming language (Pascal).

Pseudocode Terminology
The general programming language terms used in psuedocode are:
  • Terms used for input step: Input, Read
  • Terms used for output step: Output, Write, Display
  • Terms used for the assignment step: Set, Store
  • Terms used for selection: If-Else-Endif
  • Terms used for bounded iteration: For-Endfor
  • Terms used for unbounded iteration: While-Endwhile, Repeat-Until

Using the IPO chart above we can easily create a pseudocode as shown below.
Step1: Start
Step2: Input length
Step3: Input width
Step4: Area ← length*width
Step5: Output Area
Step6: Stop

Flowchart

A diagrammatic representation of an algorithm using a variety of symbols. These symbols are:
Flow chart symbols