A stack is a fundamental data structure in computer science that follows the Last-In-First-Out (LIFO) principle. In Python, a stack can be implemented using a list or the collections.deque class.

## Stack Operations

A stack supports the following operations:

**Push:** Adds an element to the top of the stack.
**Pop:** Removes and returns the top element from the stack.
**Peek:** Returns the top element from the stack without removing it.
**isEmpty:** Checks if the stack is empty or not.
**Size:** Returns the number of elements in the stack.

## Implementing a Stack in Python

In Python, we can implement a stack using a list. Let’s see an example:

```
<ul>
<li>
```__# Creating an empty stack</u>
<li>stack = []</li>
</ul>
# Pushing elements onto the stack
stack.append(1)
stack.append(2)
stack.append(3)
# Popping elements from the stack
top_element = stack.pop()
print(top_element) # Output: 3
# Peeking at the top element
top_element = stack[-1]
print(top_element) # Output: 2
# Checking if the stack is empty
is_empty = len(stack) == 0
print(is_empty) # Output: False
# Getting the size of the stack
size = len(stack)
print(size) # Output: 2__

__
__## Using collections.deque for Stack Implementation

The `collections.deque`

class in Python provides an efficient implementation of stacks. Let’s see how to use it:

`<ul>`

<li>__# Importing the deque class from the collections module</u>
__ <li>from collections import deque</li>

<li>__# Creating an empty stack</u>
__

__ <li>stack = deque()</li>__

</ul>

__
__## Conclusion

A stack is a powerful data structure that allows efficient insertion and removal of elements. In Python, you can implement a stack using a list or the `collections.deque`

class. Understanding stacks and their operations is essential for solving many computational problems.

Now that you have learned about stacks in data structures, you can start using them to solve various programming challenges efficiently.

### 8 Related Question Answers Found

Is Stack a Data Structure in Python? A stack is indeed a data structure in Python. It is an abstract data type that follows the Last-In-First-Out (LIFO) principle.

A stack is a linear data structure that follows the Last-In-First-Out (LIFO) principle. It is an ordered collection of elements where the addition and removal of items happen only at one end called the top. The element that is added last is the first one to be removed.

What Is Stack in Data Structure? A stack is a fundamental data structure in computer science that follows the Last In, First Out (LIFO) principle. It is an abstract data type that represents a collection of elements with two primary operations: push and pop.

A stack is a fundamental data structure in computer science that follows the Last-In-First-Out (LIFO) principle. It can be visualized as a stack of books where the last book placed on top is the first one to be removed. In simple words, a stack is a container that holds elements and provides two main operations: push and pop.

What Is Meant by Stack in Data Structure? A stack is a fundamental data structure in computer science that follows the Last In First Out (LIFO) principle. It can be visualized as a stack of plates where the last plate placed on top is the first one to be removed.

What Is the Concept of Stack in Data Structure? A stack is a fundamental data structure in computer science that follows the Last-In-First-Out (LIFO) principle. It is analogous to a stack of plates, where the last plate added is the first one to be removed.

What Is Stack in Data Structure Real Life Example? In the world of computer science and programming, data structures play a crucial role in organizing and managing data efficiently. One such data structure is a stack.

A stack is a fundamental data structure in computer science. It is an abstract data type that follows the Last-In-First-Out (LIFO) principle. In simple terms, this means that the last element added to the stack is the first one to be removed.