Chapter 12: Bitwise Operations – Ones, Zeros, and Mind Tricks

Table of Contents

• Table of Contents
• 12.1 Bitwise Operators
• 12.2 Common Bitwise Tricks
• 12.3 Exercises
• 12.4 Solutions
  • 12.4.1 Solution 1
  • 12.4.2 Solution 2
  • 12.4.3 Solution 3
• 12.5 What’s Coming in the Next Chapter

12.1 Bitwise Operators

• & AND
• | OR
• ^ XOR
• ~ NOT
• << left shift
• >> right shift

Example:

int a = 5 & 3; // AND

12.2 Common Bitwise Tricks

• Swapping values
• Checking even/odd
• Setting/clearing bits

12.3 Exercises

1. Write a program to check if a number is even using bitwise AND.
2. Swap two numbers using XOR.
3. What does ~0 evaluate to?

12.4 Solutions

12.4.1 Solution 1

if ((x & 1) == 0) printf("Even\n");

12.4.2 Solution 2

a = a ^ b;
b = a ^ b;
a = a ^ b;

12.4.3 Solution 3

All bits set (bitwise NOT of 0).

12.5 What’s Coming in the Next Chapter

Next, you’ll learn about C libraries and header files!

Next Chapter → C Libraries and Header Files