Control Flow Statements (if-else, loops) in C

Welcome to the tutorial on control flow statements in C. Control flow statements allow you to control the flow of execution in your programs based on certain conditions or loops. In this tutorial, we will explore if-else statements and loops in detail. Let's get started:

Introduction to Control Flow Statements

In programming, control flow refers to the order in which statements are executed. Control flow statements in C enable you to make decisions and repeat a block of code multiple times based on specific conditions. They allow you to create more complex and dynamic programs.

If-Else Statements

The if-else statement is used to make decisions in your program based on a condition. It allows you to execute a block of code if the condition is true, and an optional block of code if the condition is false. Here's an example:


int age = 25;

if (age >= 18) {

    printf("You are an adult.");

} else {

    printf("You are a minor.");

}

In the above example, the if-else statement checks if the variable age is greater than or equal to 18. If it is, the program prints "You are an adult." Otherwise, it prints "You are a minor."

Loops

Loops are used to repeat a block of code multiple times until a certain condition is met. C provides three types of loops: while, do-while, and for. Here are examples of each:


// While Loop

int count = 0;

while (count < 5) {

    printf("Count: %d\n", count);

    count++;

}



// Do-While Loop

int i = 0;

do {

    printf("i: %d\n", i);

    i++;

} while (i < 5);



// For Loop

for (int j = 0; j < 5; j++) {

    printf("j: %d\n", j);

}

In the above examples, the while loop and do-while loop repeatedly execute a block of code as long as the condition is true. The for loop provides a compact way to initialize, test, and update a loop variable in a single line.

Common Mistakes with Control Flow Statements in C

Missing braces ({}) around the blocks of code in if-else statements or loops.
Forgetting to update the loop variable in a loop, resulting in an infinite loop.
Using assignment (=) instead of comparison (==) in conditions.

Frequently Asked Questions (FAQs)

Q1: Can I nest if-else statements and loops?

A1: Yes, you can nest if-else statements and loops within each other to create more complex control flow structures.

Q2: What is the difference between the while loop and the do-while loop?

A2: The while loop checks the condition before executing the loop, while the do-while loop executes the loop at least once before checking the condition.

Q3: How do I exit a loop prematurely?

A3: You can use the break statement to exit a loop prematurely based on a certain condition.

Q4: Can I use multiple conditions in an if-else statement?

A4: Yes, you can use multiple conditions using logical operators such as && (AND) and || (OR).

Q5: How can I skip the current iteration of a loop?

A5: You can use the continue statement to skip the current iteration of a loop and move to the next iteration.

Summary

In this tutorial, we learned about control flow statements in C. We explored if-else statements and how they allow you to make decisions based on conditions. We also discussed the different types of loops in C, including the while loop, do-while loop, and for loop, and how they enable you to repeat a block of code multiple times. We covered common mistakes that people make with control flow statements and provided answers to frequently asked questions. By understanding control flow statements, you now have the knowledge to create more dynamic and efficient C programs.