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);
newNode.next = this.top;
this.top = newNode;
if (this.length === 0) {
this.bottom = newNode;
}
this.length++;
return this;
}
pop() {
if (this.length <= 1) {
this.top = null;
this.bottom = null;
this.length = Math.max(this.length-1,0);
return this;
}
const secondLast = this.top.next;
delete this.top;
this.top = secondLast || this.bottom;
this.length--;
return this;
}
}
const stack = new Stack();
stack.push(10);
stack.push(12);
stack.push(11);
stack.push(14);
// stack.pop();
// stack.pop();
// stack.pop();
// stack.pop();
// stack.pop();
// stack.pop();
// stack.pop();
console.log(stack.pop());
console.log(stack.peek())
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 holdingPointer;
}
}
const stack = new Stack();
stack.push(10);
stack.push(12);
stack.push(11);
stack.push(14);
stack.pop();
// stack.pop();
// stack.pop();
// stack.pop();
// stack.pop();
// stack.pop();
// stack.pop();
console.log(stack.pop());
