The ultimate guide to bit manipulation for coding interviews. Developed by FAANG engineers, practice with real-world interview questions, and get interview-ready in just a few hours.

This course teaches bit manipulation, a powerful technique to enhance algorithmic and problem-solving skills. It is a critical topic for those preparing for coding interviews for top tech companies, startups and industry leaders. Competitive programmers can take full advantage of this course by running most of the bit-related problems in O(1) complexity.

The course will begin by educating you about the number system and its representation, decimal and binary, followed by the six bitwise operators: AND, OR, NOT, XOR, and bit-shifting (left, right).

You will receive ample practical experience working through practice problems to improve your comprehension.

Upon completing this course, you will be able to solve problems with greater efficiency and speed.

Grokking Bit Manipulation for Coding Interviews

# Introduction

In this question, we take input and switch its sign.

# Problem Statement
We need to write a program to switch the sign of a number.

```
Input: 10
 
Output: -10

``` 


# Solution

We already know that 2's complement of any number gives a negative number with the formula below.

**Formula**
>  ~x = ($2^{32}$ - x) 

For example,
```
 >if, x = 1
    ~x = -2

 if, y = 10
    ~y = -11
```

So if you see the pattern, the number is negated and converted to 2's complement.

```
    number  = 8
   ~number  = -9
----------------------------
~number + 1 = (-9 + 1) = -8
----------------------------
```



In this lesson, we make use of the NOT operator to switch the sign of a number.

Getting Started

Number Systems, Bitwise, and Binary

Bitwise AND

Bitwise OR

Bitwise NOT

Bitwise XOR

Bit Shifting - Left, Right

Bitwise LeftShift Problems

Bitwise RightShift Problems

Final Thoughts

Switch Sign of a Number

Introduction

Problem Statement

Solution