This lesson is all about learning to think like a computer programmer. The goal is to break down a problem into simple, logical steps that a computer can follow.

Short Notes

• Problem Analysis: Every problem has three parts:

  • Input: The data or materials you start with (e.g., two numbers to add).

  • Process: The steps you take to solve the problem (e.g., the action of adding).

  • Output: The final result (e.g., the sum).

• Algorithm: An algorithm is a clear, step-by-step plan for solving a problem.

• Control Structures: These are the building blocks of algorithms.

  • Sequence: Steps are performed one after another in a strict order.

  • Selection: A decision is made. If a condition is true, one path is taken; if not, another path is taken (e.g., IF...THEN...ELSE).

  • Repetition (Iteration): A set of steps is repeated until a condition is met (e.g., WHILE something is true, REPEAT a task UNTIL a goal is reached).

• Flowcharts: A visual way to represent an algorithm using standard symbols.

• Pseudo-code: Writing out the steps of an algorithm in simple English-like statements before writing it in a real programming language.

• Pascal Basics:

  • Identifier: A name you give to something, like a variable (e.g., student_name).

  • Variable: A placeholder for a value that can change (e.g., total_marks).

  • Constant: A value that does not change (e.g., pi = 3.14).

  • Data Types: Integer (whole numbers), Real (decimal numbers), Char (a single character like 'A'), String (text like "Hello"), Boolean (True or False).

Important Points for the Exam

• Memorize the flowchart symbols! You will likely be asked to draw a simple flowchart or interpret one.

• Understand the three Control Structures. Be able to identify which one is being used in a given problem (Sequence, Selection, or Repetition).

• For Selection, know the difference between a simple IF...THEN and an IF...THEN...ELSE structure.

• For Repetition, understand when to use a FOR loop (when you know the number of repeats) versus a WHILE loop (when you don't).

• You don't need to be a Pascal expert, but you should be able to read a simple piece of code and identify variables, data types, and what the code is trying to achieve.

Tips & Tricks for Studying

• Practice with Everyday Tasks: Write the algorithm and draw a flowchart for making a cup of tea or calculating your bus fare. This makes the concepts easier to understand.

• Trace the Code: When you see a piece of Pascal code, pretend you are the computer. Write down the variables and track how their values change line by line.

• Think Logically: Programming questions are logic puzzles. Read the question carefully to understand the required inputs, the exact process, and the desired output before you start designing a solution.