Chapter 5: Functions – Divide and Conquer

Table of Contents

• Table of Contents
• 5.1 Defining and Calling Functions
• 5.2 Function Parameters and Return Values
• 5.3 Exercises
• 5.4 Solutions
  • 5.4.1 Solution 1
  • 5.4.2 Solution 2
  • 5.4.3 Solution 3
• 5.5 What’s Coming in the Next Chapter

5.1 Defining and Calling Functions

Functions help you break your code into reusable pieces:

int add(int a, int b) {
    return a + b;
}

int main() {
    int sum = add(2, 3);
    printf("Sum: %d\n", sum);
    return 0;
}

5.2 Function Parameters and Return Values

You can pass values to functions and get results back. Functions can have multiple parameters and return a value.

5.3 Exercises

1. Write a function that multiplies two numbers.
2. Write a function that returns the maximum of two integers.
3. What happens if you forget to return a value from a non-void function?

5.4 Solutions

5.4.1 Solution 1

int multiply(int a, int b) {
    return a * b;
}

5.4.2 Solution 2

int max(int a, int b) {
    return (a > b) ? a : b;
}

5.4.3 Solution 3

The returned value is undefined; the result may be garbage.

5.5 What’s Coming in the Next Chapter

Next, you’ll learn about pointers—one of C’s most powerful features!

Next Chapter → Pointers – Handle With Care