Computer Science Notes

Algorithm and Flowchart: Definition, Steps, Examples, Advantages & Disadvantages

This post explains Algorithm and Flowchart in simple English—definition, steps, real-world examples, pros & cons, a difference table, and FAQs. Perfect for students and exam preparation! ✅

Beginner Friendly With Examples Quick Revision

Introduction

Before creating software, it’s important to plan how a problem will be solved. An Algorithm describes logical steps in text, while a Flowchart represents those steps visually with diagrams. Together, they make problem solving easier to understand and communicate.

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What is an Algorithm?

Definition: An algorithm is a finite, well-defined sequence of steps that provides a solution to a specific problem.

Properties of a Good Algorithm

Input/Output: Clearly defined inputs and expected outputs.
Definiteness: Each step must be precisely defined.
Finiteness: Must terminate after a finite number of steps.
Effectiveness: Steps should be practical and doable.
Generality: Should apply to a broad set of similar problems.

What is a Flowchart?

Definition: A flowchart is a diagram that visually represents the steps of an algorithm using **symbols** (Start/End, Process, Decision, Input/Output, Arrows).

Common Symbols

Oval: Start/End
Rectangle: Process/Instruction
Diamond: Decision (Yes/No)
Parallelogram: Input/Output
Arrow: Flow direction

Basic Steps (Pseudocode)

Example: Sum of two numbers

START
  READ A, B
  SUM ← A + B
  PRINT SUM
END

Flowchart idea: Start → Input A,B → Process A+B → Output SUM → End

Example 1: Find Maximum of Two Numbers

START
  READ X, Y
  IF X > Y THEN
     PRINT X
  ELSE
     PRINT Y
  ENDIF
END

Flowchart: Start → Input (X,Y) → Decision (X>Y?) → Print X / Print Y → End

Example 2: Factorial (n!)

START
  READ n
  FACT ← 1
  FOR i ← 1 TO n
     FACT ← FACT × i
  ENDFOR
  PRINT FACT
END

Flowchart: Start → Input n → Loop (i=1..n) → Update FACT → Output FACT → End

Advantages & Disadvantages

Advantages of Algorithms

Provides a clear and structured problem-solving method.
Removes ambiguity—every step is defined.
Easy to test and debug.
Reusable for similar problems.
Language independent (implementation flexibility).

Disadvantages of Algorithms

Can become lengthy for complex problems.
Lacks visualization—harder to explain quickly.
May not show

Comparison: Algorithm vs Flowchart (Advantages & Disadvantages)

	Algorithm	Flowchart
Advantages	Clear and structured problem-solving method Easy to test and debug Reusable for similar problems Language independent Precise and well-defined steps	Visual representation makes it easier to understand Errors can be identified quickly Good for documentation and training Improves communication in teams Gives an overview of the complete process
Disadvantages	Becomes lengthy for complex problems No visualization (only text) May not reflect real-world constraints	Large problems create very complex diagrams Difficult and time-consuming to update Does not show coding-level details Requires knowledge of symbols

Tags: c programming

Algorithm and Flowchart Explained with Examples and advantages and disadvantages