COMPINTRO ALGORITHM & PSEUDOCODE

lessons 5&6

Algorithm

a set of well-defined instructions to solve a particular problem. It takes a set of input(s) and produces the desired output. 

Qualities of a good algorithm

• Input and output should be defined precisely.

• Each step in the algorithm should be clear and unambiguous.

• Algorithms should be most effective among many different ways to solve a problem.

• An algorithm shouldn't include computer code. Instead, the algorithm should be written in such a way that it can be used in different programming languages.

• Consist of clear, practical steps executable in limited time by a person or machine.

• Be unambiguous, with defined steps, including decision points (e.g.,“if” statements).

• Have a finite number of steps, using loops for repeated actions.

• Reach an endpoint, avoiding infinite loops.

How does Algorithm work

take a set of initial data or input, process it through a series of logical steps or rules, and generates an output, which can be the outcome, decision, or result.

Types of algorithms or control flow

1. Linear Sequence Algorithm

2. Conditional Algorithm

3. Looping Algorithms

Types of algorithms or control flow: Linear Sequence Algorithm

follow a specific set or steps, one after the other.

Types of algorithms or control flow: Conditional Algorithm

make a decision between two actions.

Types of algorithms or control flow: Looping Algorithms

repeat a specific set of instructions multiple types until either a certain condition is met or a predefined number of repetitions has been completed.

Pseudocode

 defined as a step-by-step description of an algorithm. Pseudocode does not use any programming language in its representation instead it uses the simple English language text as it is intended for human understanding rather than machine reading.

Main constructs of pseudocode

1. SEQUENCE

2. WHILE

3. REPEAT-UNTIL

4. FOR

5. IF-THEN-ELSE

6. CASE

Main constructs of pseudocode : SEQUENCE

• INPUT: READ , OBTAIN, GET

• OUTPUT: PRINT, DISPLAY, SHOW

• COMPUTE: COMPUTE, CALCULATE, DETERMINE

• INITIALIZE: SET, INIT

• ADD: INCREMENT

• SUB: DECREMENT

Main constructs of pseudocode : FOR

Main constructs of pseudocode : WHILE

Main constructs of pseudocode :CASE

Main constructs of pseudocode : REPEAT-UNTIL

Main constructs of pseudocode :IF-THEN-ELSE

Extra constructs of Pseudocode

1. CALLING CLASSES or FUNCTIONS

2. EXCEPTION HANDLING

Extra constructs of Pseudocode:CALLING CLASSES or FUNCTIONS

Extra constructs of Pseudocode:EXCEPTION HANDLING