05.Looping

Chapter 5: Looping Overview

• Examines various types of loops in programming, particularly focusing on their structure and functionality.

Types of Loops

While Loops

• Definition: A pre-test loop that checks a condition before each iteration.

• Structure:

  • Consists of a boolean condition and a block of statements.

• Example:

  while (boolean_expression) {
      // Statements executed if true
  }

• Can execute zero times if the condition is false on the first check.

Do-While Loops

• Definition: Similar to the while loop, but checks the condition after the block executes, guaranteeing at least one execution.

• Structure:

  do {
      // Statements to execute
  } while (boolean_expression);

For Loops

• Designed for a specific type of counting iteration.

• Structure:

  for (initialization; condition; update) {
      // Statements executed each iteration
  }

• Combines initialization, condition checking, and update statement in one line.

Looping Mechanics

Conditional Execution vs. Repeated Execution

• Conditional Structures execute based on true/false (if, switch).

• Repetition Structures execute multiple times based on user decision or condition.

Iteration

• Definition: A single execution of the loop body.

• Infinite loops occur when the loop does not exit, usually due to unchecked conditions.

Input Validation with While Loops

• Validates user input within a loop until valid input is obtained.

• Example:

  while (condition) {
      // Prompt and receive input
  }

Increment and Decrement Operators

• Increment: ++ operator increases a variable's value by one.

• Decrement: -- operator decreases a variable's value by one.

Nested Loops

• Definition: Loops within loops; each complete iteration of the outer loop may run the entire inner loop.

• Applications:

  • Processing multi-dimensional data, such as grids or tables.

  • Handling collections of items systematically.

Loop Control Keywords

Break and Continue

• Break: Exits the current loop entirely.

• Continue: Skips the current iteration and returns to condition checking.

File Handling

File Streams

• Basic file handling relies on ifstream for input and ofstream for output.

File Opening

• Files are opened using the .open() method.

  ifstream file(