# Challenge 1: Count Set Bits

This is a traditional problem counting the number of set bits or 1's present in a number.

## Introduction

Let’s see how we can count the set bits using the **AND** operator.

### What are set-bits?

1 = set-bit

0 = unset-bit

For example:

```
Input: 5
Output: 0101 (in binary)
```

There are two set bits are two in the above example, as we have two 1’s in the binary representation.

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