Overview of Repetitive Execution and the Need for Loops

In programming, we often encounter situations where we need to execute a block of code multiple times. Imagine calculating the average of a hundred numbers, printing a multiplication table, or processing data from a large file. Without a mechanism for repetition, we would have to write the same code block over and over again, which is tedious, error-prone, and inefficient. This is where loops come into play.

Loops provide a way to execute a block of code repeatedly until a specific condition is met. They automate repetitive tasks, making our code concise, readable, and easier to maintain. Instead of writing the same set of instructions hundreds of times, we can encapsulate those instructions within a loop and tell the program how many times to repeat them.

Control Flow and Iteration

Loops introduce a vital concept called control flow. Control flow refers to the order in which statements in a program are executed. Loops change the standard sequential execution of code by allowing us to jump back to a previous point and re-execute a section.

Each execution of the code block within a loop is called an iteration. During each iteration, the program executes the statements inside the loop's body. The loop continues to iterate until the specified condition becomes false. This condition is crucial because it determines when the loop should terminate, preventing it from running indefinitely (an infinite loop).

C provides several types of loops, each designed for different scenarios and offering varying degrees of control over the iteration process. The most common types of loops in C are:

• for loop: Ideal when you know in advance how many times you need to execute the loop.
• while loop: Suitable when you want to execute the loop as long as a condition is true.
• do-while loop: Similar to the `while` loop, but guarantees that the loop body will execute at least once.

Next Steps

The following sections will delve into each of these loop types in detail, providing examples and explanations to help you understand how to use them effectively in your C programs.