Algorithms and Flowcharts

An algorithm is a step-by-step procedure or set of rules designed to solve a specific problem or perform a computation. In computer science, it serves as the blueprint for writing a program. For board exams, you must remember that a good algorithm must be precise, finite, and unambiguous. It typically starts with a Start step, takes specific inputs, executes logical or mathematical operations step-by-step, and terminates with an Stop or Output step. Writing algorithms for basic mathematical problems (like finding the sum of three numbers, calculating the area of a circle, or finding the factorial of a number) is a frequent long-question requirement in paper patterns.

A flowchart is the graphical or pictorial representation of an algorithm. It uses standardized geometric symbols connected by flowlines to show the direction of execution. Memorizing the standard flowchart symbols and their specific functions is crucial for multiple-choice questions (MCQs) and short questions. The most commonly tested symbols include the Terminal (oval for start/stop), Input/Output (parallelogram), Processing (rectangle for calculations), Decision (diamond for conditions and branching), and Flowlines (arrows showing the sequence).

Problem-solving in this chapter also relies heavily on control structures, which dictate the flow of execution in both algorithms and flowcharts. These include sequence (statements executed one after another), selection (making decisions using IF-THEN-ELSE logic represented by diamond boxes), and iteration/looping (repeating a set of steps until a condition is met). Board exams frequently test your ability to convert a simple word problem into both an algorithm and its corresponding flowchart, or to trace a flowchart to find its output. Pay special attention to drawing neat, well-connected flowcharts with clear arrowheads, as examiners deduct marks for ambiguous flow directions.