public class Main {

    public static void main(String[] args) {
        Node list = new Node();
        list.insert_node_at_beginning(10);
        list.insert_node_at_beginning(20);
        list.insert_node_at_beginning(30);
        list.print();
        list.insert_node_at_end(40);
        list.insert_node_at_end(50);
        list.print();
        list.delete_node(10);
        list.delete_node(50);
        list.print();
    }
}
class Node {
    Node head; // first node in the List
    Node next;
    int info; // storing bunch of integers
    Node() {
        head = null;
        next = null;
    }
    Node(int x) {
        info = x;
        next = null;
    }
    public void insert_node_at_beginning(int x) { // data which the new node will store
        if(head == null) { // empty linked list
            head = new Node(x);
            return;
        }
        Node new_node = new Node(x);
        new_node.next = head;
        head = new_node;
    }
    public void insert_node_at_end(int x) { // at the end insert a node
        Node new_node = new Node(x);
        Node tmp = head;
        while(tmp.next != null) {
            tmp = tmp.next;
        }
        tmp.next = new_node;
        new_node.next = null;
    }
    public void delete_node(int x) { // data which should get deleted
        Node tmp = head;
        Node prev = null; // previous node
        while(tmp.info != x) { // iterate through the list till the node which should get deleted
            prev = tmp;
            tmp = tmp.next;
        }
        prev.next = tmp.next;
    }
    public void print() {
        Node tmp = head;
        while(tmp != null) {
            System.out.print(tmp.info + "-> ");
            tmp = tmp.next;
        }
        System.out.println();
    }

}