Implementing JavaScript Stack Using Array

Implementing a JavaScript stack using an array is relatively straightforward. A stack follows the Last-In-First-Out (LIFO) principle, meaning the most recently added item is the first one to be removed.

Sure! Here’s an implementation of a stack data structure using an array in JavaScript:

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

  // Push an element onto the stack
  push(element) {
    this.items.push(element);
  }

  // Pop the top element from the stack and return it
  pop() {
    if (this.isEmpty()) {
      return null;
    }
    return this.items.pop();
  }

  // Return the top element of the stack without removing it
  peek() {
    if (this.isEmpty()) {
      return null;
    }
    return this.items[this.items.length - 1];
  }

  // Check if the stack is empty
  isEmpty() {
    return this.items.length === 0;
  }

  // Return the size of the stack
  size() {
    return this.items.length;
  }

  // Clear the stack
  clear() {
    this.items = [];
  }
}

// Example usage
const stack = new Stack();

stack.push(10);
stack.push(20);
stack.push(30);

console.log(stack.peek()); // Output: 30

console.log(stack.pop()); // Output: 30

console.log(stack.size()); // Output: 2

console.log(stack.isEmpty()); // Output: false

stack.clear();
console.log(stack.isEmpty()); // Output: true

In this implementation, the Stack class has an items array that stores the elements of the stack. The class provides several methods to manipulate the stack:

• push(element): Pushes an element onto the stack by adding it to the end of the items array.
• pop(): Pops the top element from the stack by removing and returning the last element of the items array.
• peek(): Returns the top element of the stack without removing it by accessing the last element of the items array.
• isEmpty(): Checks if the stack is empty by verifying if the items array has a length of 0.
• size(): Returns the number of elements in the stack by returning the length of the items array.
• clear(): Clears the stack by setting the items array to an empty array.

You can create a new instance of the Stack class and use its methods to perform stack operations such as pushing, popping, peeking, checking emptiness, getting the size, and clearing the stack.