使用Node类为Stack类创建push()方法

class Node {
  constructor(value) {
    this.value = value;
    this.next = null;
  }
}

class Stack {
  constructor() {
    this.top = null;
    this.size = 0;
  }

  push(value) {
    const newNode = new Node(value);
    newNode.next = this.top;
    this.top = newNode;
    this.size++;
  }

  // 其他方法如 pop(), peek(), isEmpty() 等可以根据需要实现
}

// 示例使用
const stack = new Stack();
stack.push(1);
stack.push(2);
stack.push(3);
console.log(stack.top.value); // 输出 3
console.log(stack.size); // 输出 3

pop() {
  if (this.isEmpty()) {
    throw new Error("Stack is empty");
  }
  const poppedValue = this.top.value;
  this.top = this.top.next;
  this.size--;
  return poppedValue;
}

isEmpty() {
  return this.size === 0;
}