Control Structures in Programming

Control Structures

• Control structures are used to control the flow of a program.
• They provide a way to execute specific blocks of code based on conditions.
• There are six main control structures: Blocks, While Loops, Do While Loops, For Loops, If Statements, and Switch Statements.

Blocks

• A block is a group of statements enclosed in curly braces ({}).
• They define a scope, which determines the visibility of variables within that block.
• Variables declared within a block are only accessible within that block and any sub-blocks.

While Loops

• While loops repeat a block of code as long as a boolean expression evaluates to true.
• The expression is checked before each iteration.
• If the expression never becomes false, the loop will continue indefinitely (infinite loop).
• It is important to ensure that some condition inside the loop is changed to make the expression false eventually.

If Statements

• If statements allow the program to execute different sets of code based on a condition.
• They can have an optional else clause to specify code to execute if the condition is false.
• The if block is executed if the boolean expression evaluates to true.
• The else block is executed if the boolean expression evaluates to false.

Algorithm Development

• An algorithm is a set of unambiguous steps that can be followed to solve a problem.
• It is similar to a program, but algorithms always terminate.
• Pseudocode can be used to represent the steps in an algorithm before translating it to code.

Pseudocode and Refinement

• Pseudocode is a way of writing the algorithm's steps using a combination of English and programming concepts.
• It can be refined progressively by breaking down steps into smaller, more concrete sub-steps.
• This process allows for a gradual development of a program's logic.

Program Development Steps

• The program development process involves a series of steps:
  • Designing the algorithm: Define the steps needed to solve the problem.
  • Coding the algorithm: Translate the pseudocode into a programming language.
  • Compiling: Check for syntax errors and convert the code into machine-readable instructions.
  • Testing: Run the program and test its functionality.
  • Debugging: Identify and fix errors in the program.