class Node {
constructor(value){
this.value = value;
this.next = null;
}
}
class Stack {
constructor(){
this.top = null;
this.bottom = null;
this.length = 0;
}
peek() {
return this.top;
}
push(value){
const newNode = new Node(value);
if (this.length === 0) {
this.top = newNode;
this.bottom = newNode;
} else {
const holdingPointer = this.top;
this.top = newNode;
this.top.next = holdingPointer;
}
this.length++;
return this;
}
pop(){
if (!this.top) {
return null;
}
if (this.top === this.bottom) {
this.bottom = null;
}
const holdingPointer = this.top;
this.top = this.top.next;
this.length--;
return this;
}
//isEmpty
}
const myStack = new Stack();
myStack.peek();
myStack.push('google');
myStack.push('udemy');
myStack.push('discord');
myStack.peek();
myStack.pop();
myStack.pop();
myStack.pop();
//Discord
//Udemy
//google
