Queue Operations

In this section, we will discuss the operations associated with queues: enqueue, dequeue, and peek.

Enqueue Operation

The enqueue operation adds an element to the end of the queue. It increases the size of the queue by one and places the new element at the rear.

In the implementation of a queue, the enqueue operation can be performed by using the append method in Python to add the element to the rear of the list.

Here is an example of how the enqueue operation works in Python:

1queue = []
2queue.append(1)
3queue.append(2)
4queue.append(3)
5
6print(queue)  # Output: [1, 2, 3]

Dequeue Operation

The dequeue operation removes the element from the front of the queue and returns it. It decreases the size of the queue by one.

In the implementation of a queue, the dequeue operation can be performed by using the pop method with an index of 0 to remove and return the front element of the list.

Here is an example of how the dequeue operation works in Python:

1queue = [1, 2, 3]
2
3print(queue.pop(0))  # Output: 1
4print(queue)  # Output: [2, 3]

Peek Operation

The peek operation returns the front element of the queue without modifying the queue. It does not change the size of the queue.

In the implementation of a queue, the peek operation can be performed by accessing the element at index 0 in the list.

Here is an example of how the peek operation works in Python:

1queue = [1, 2, 3]
2
3print(queue[0])  # Output: 1
4print(queue)  # Output: [1, 2, 3]

It is important to note that performing the dequeue or peek operation on an empty queue will result in an error.

Now that we have a good understanding of the queue operations, we can move on to the next section where we will learn about stack applications in robotics and computer vision.

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    print("Front of queue:", peek(queue))

if __name__ == "__main__":

    # Create an empty queue

def create_queue():

    queue = []

    return queue

​

# Function to add an item to the queue

def enqueue(queue, item):

    queue.append(item)

    print("Enqueued item:", item)

​

# Function to remove an item from the queue

def dequeue(queue):

    if len(queue) < 1:

        return None

    return queue.pop(0)

​

# Function to get the front item in the queue

def peek(queue):

    if len(queue) < 1:

        return None

    return queue[0]

​

# Main function

if __name__ == "__main__":

    queue = create_queue()

    enqueue(queue, 1)

    enqueue(queue, 2)

    enqueue(queue, 3)