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# Python Program to Implement Queue

In this Python program, we will implement a queue data structure using a list. A queue follows the First-In-First-Out (FIFO) principle, where the element added first is the one that will be removed first.

## Problem Statement

Implement a queue data structure using a list and provide methods to enqueue (add) elements to the rear and dequeue (remove) elements from the front of the queue.

## Python Program to Implement Queue

```class Queue:
def __init__(self):
self.queue = []

def enqueue(self, item):
self.queue.append(item)

def dequeue(self):
if not self.is_empty():
return self.queue.pop(0)
else:
return "Queue is empty"

def is_empty(self):
return len(self.queue) == 0

def size(self):
return len(self.queue)

# Example usage
if __name__ == "__main__":
q = Queue()
q.enqueue(10)
q.enqueue(20)
q.enqueue(30)

print("Queue size:", q.size())
print("Dequeued:", q.dequeue())
print("Dequeued:", q.dequeue())
print("Queue size:", q.size())
print("Dequeued:", q.dequeue())
print("Is empty:", q.is_empty())
print("Dequeued:", q.dequeue())
print("Is empty:", q.is_empty())
```

## How It Works

• The `Queue` class is defined with methods to perform queue operations.
• The `enqueue` method appends the given item to the end of the queue.
• The `dequeue` method removes and returns the first item from the front of the queue.
• The `is_empty` method checks if the queue is empty.
• The `size` method returns the current size of the queue.

## Input/Output

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