# Which Data Structure Uses Stack?

//

Larry Thompson

When it comes to data structures, the stack is a popular choice for many applications. A stack is a linear data structure that follows the Last-In-First-Out (LIFO) principle.

This means that the last element added to the stack will be the first one to be removed. In other words, it works like a stack of plates – you can only remove the topmost plate at any given time.

## Why Use a Stack?

A stack is efficient when you need to keep track of elements in a specific order and perform operations like push (add an element), pop (remove an element), and peek (access the topmost element) quickly. Its simplicity and fast operations make it an excellent choice for various applications.

## Applications of Stacks

Here are some common scenarios where using a stack can greatly simplify your problem:

• Function Call Stack: When a function is called, its return address and local variables are stored in a stack frame. This allows for easy management of function calls and returns.
• Expression Evaluation: Stacks are commonly used to evaluate arithmetic expressions. Operators and operands are pushed onto the stack and processed according to their priority.
• Backtracking: In algorithms like depth-first search or backtracking, stacks can help store previous states or choices made, allowing for easy backtracking when necessary.
• Undo/Redo Operations: Stacks can be used to implement undo/redo functionality in applications by storing previous states or actions performed by the user.

## The Stack Data Structure

In programming languages, stacks can be implemented using arrays or linked lists. Here’s an example of a stack implemented using an array:

``````
class Stack {
constructor() {
this.items = [];
}

push(element) {
this.items.push(element);
}

pop() {
if (this.isEmpty()) {
return "Underflow";
}
return this.pop();
}

peek() {
return this.items[this.length - 1];
}

isEmpty() {
return this.length === 0;
}
}
```
```

## Conclusion

In conclusion, the stack data structure is well-suited for scenarios where you need to keep track of elements in a specific order and perform quick operations like push, pop, and peek. Its simplicity and efficient operations make it a valuable choice in various applications. Whether you’re working with function calls, expression evaluation, backtracking, or undo/redo operations, using a stack can greatly simplify your problem.