fin bug in stack

[AadityaThantharate]

import java.util.*;

public class Main {
// static class Node {
// int data;
// Node next;

//     public Node(int data) {
//         this.data = data;
//         next = null;
//     }

// }

// static class Stack {
//     public static Node head;

//     public static boolean isEmpty() {
//         return head == null;
//     }

//     public static void push(int data) {
//         Node newNode = new Node(data);
//         if (isEmpty()) {
//             head = newNode;
//             return;
//         }
//         newNode.next = head;
//         head = newNode;
//     }

//     public static int pop() {
//         if (isEmpty()) {
//             return-1;
//         }

//             int top = head.data;
//             head = head.next;
//             return top;
        
//     }

//     public static int peek() {
//         if (isEmpty()) {
//             return -1;
//         }
//         return head.data;
//     }
// }

// By Array List
static class Stack {
    static ArrayList<Integer> list = new ArrayList<>();
    public static boolean isEmpty(){
        return list.size() ==0;
    }
    //push
    public static void push(int data){
        list.add(data);
    }
    public static int pop(){
        if(isEmpty()){
            return -1;
        }
        int top = list.get(list.size()-1);
        list.remove(list.size()-1);
        return top;
    }
    public static int peek(){
        if(isEmpty()){
            return -1;
        }
        return  list.get(list.size()-1);
    }
}
public static void main(String[] args) {
    Stack s = new Stack();
    s.push(1);
    s.push(2);
    s.push(3);
    s.push(4);

    while(!s.isEmpty()) {
        System.out.println(s.peek());
        s.pop();
    }
}

}

When i ever try to create stack it show me error continuosly you can see my code in i try to run the code in online copiler and its perfectly running properly see what happend and informed idk what kind of bug or error i am facing