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Difference Between Push and Pop in Stack

Introduction:

Data Structures are used for easy access to elements. Stacks and queues are dynamic and linear data structures.

Stack has only one entry point whereas queue has entry and exit points. We can, for instance, consider an idly maker as a stack. In idly maker we will arrange the plates in such a way that the first inserted plate is taken out at last and the last inserted taken out first. Thus, it uses the LIFO Principle. The acronym for LIFO is Last-In-First-Out.

For instance, we can consider the luggage checking machine as a queue. In this instance, the luggage which is put on first will be checked and sent first. It uses the FIFO principle. The acronym for FIFO is First-In-First-Out.

Stack Data Structure:

We can perform many operations on stack data structures. The two main operations on the stack are Push and Pop.

Difference Between Push and Pop in Stack

Push Operation:

The "push" operation involves adding an element to the top of the stack. This action increases the stack size by one and positions the new element at the top, becoming the most recently added item. The process of pushing an element onto the stack is analogous to placing an object on top of a vertical stack of items.

We need to keep in mind that only performing push operations on stack leads to stack overflow.

Pop Operation:

The "pop" operation involves removing the top element from the stack. This action decreases the stack size by one, and the element that was most recently added becomes inaccessible. It is similar to taking the top item off a physical stack of objects.

The continuous pop operation will empty the stack.

LIFO:

Undo Mechanism: In applications like text editors and graphic design software, stacks are employed to implement the "undo" mechanism. Each action is pushed onto the stack, and popping reverses the last action.

Real-time example to demonstrate push and pop operation in the stack:

For instance, we can consider web browsing history to illustrate push and pop operations on a stack. In web browsing, as we navigate through different web pages, the new web page is added to the top of the stack. When we click the back button or undo over operation, the most recently visited page is removed and displayed. Thus, this allows us to easily navigate back through web browsing history.

Difference Between Push and Pop in Stack

Algorithm for push operation:

Algorithm for pop operation:

Code Implementation:

Output:

Difference Between Push and Pop in Stack

Push and Pop Operations:

Push Pop
Adds an inserted element to the highest point of the stack. Eliminates the last inserted or the top element from the stack.
Push activity will build the size of the stack. The pop activity will diminish the size of the stack.
We give the element to be added as the input as our parameter to the push function. We don't provide any parameter to the pop function.
On performing a push operation no output is produced. On performing a pop operation the element removed becomes the output.
Stack Overflow Exception happens assuming that the stack is full. Stack Underflow Exception happens assuming the stack is unfilled.
Time complexity: O(1). Time complexity: O(1).
Example:
Pushing a plate into a stack of plates.
Example:
Removing the top plate from the stack of plates.

Applications:

Many algorithms, such as depth-first search in graphs and certain parsing algorithms, are implemented using stacks. The push and pop operations are integral to the execution of these algorithms.

Conclusion:

In conclusion, push and pop operations are fundamental to the functionality and efficiency of stacks. Pushing adds elements to the top, expanding the stack, while popping removes the top element, providing access in a Last In, First Out manner. These operations are crucial in various applications, including memory management, algorithm implementation, and maintaining sequential order. Understanding the distinctions and implications of push and pop is essential for leveraging the power of stacks in diverse computing scenarios.







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