IP to CIDR

Question

# IPv4 Iterator and CIDR Problem

This question explores how IPv4 addresses can be represented, iterated over, and compressed into CIDR (Classless Inter-Domain Routing) blocks.  
You will start with simple iteration, move to CIDR-aware traversal, and finally discuss how to scale it to massive IP ranges efficiently.

---

## Background

An **IPv4 address** is a 32-bit unsigned integer written in dotted-decimal notation, e.g.:
```
192.168.0.1
```
Internally, this is stored as:
```
192 * 256³ + 168 * 256² + 0 * 256 + 1 = 3232235521
```
Each part (called an **octet**) represents 8 bits.  
Since an 8-bit binary number ranges from `00000000` (0) to `11111111` (255),  
each segment in an IPv4 address is between **0 and 255**.

---

## Question 1 – Implement a Forward IPv4 Iterator

Implement a class `IPv4Iterator` that iterates through IPv4 addresses sequentially starting from a given IP.

**Example**
```python
ip = IPv4Iterator("255.255.255.250")
for i in ip:
    print(i)
```

**Expected Output**
```
255.255.255.250,

255.255.255.251,

255.255.255.252,

255.255.255.253,

255.255.255.254,

255.255.255.255,
```

**Requirements**
- Implement `__init__` and `__next__`.
- Convert the IP into

Accepted Answer

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