Singly Linked List

public class SinglyLinkedList {
    Node head;
    
    // Insert at beginning
    public void insertAtHead(int data) {
        Node newNode = new Node(data);
        newNode.next = head;
        head = newNode;
    }
    
    // Insert at end
    public void insertAtEnd(int data) {
        Node newNode = new Node(data);
        if (head == null) {
            head = newNode;
            return;
        }
        Node temp = head;
        while (temp.next != null) {
            temp = temp.next;
        }
        temp.next = newNode;
    }
    
    // Delete node with given value
    public void delete(int key) {
        if (head == null) return;
        if (head.data == key) {
            head = head.next;
            return;
        }
        Node temp = head;
        while (temp.next != null && temp.next.data != key) {
            temp = temp.next;
        }
        if (temp.next != null) {
            temp.next = temp.next.next;
        }
    }
    
    // Traverse and print
    public void printList() {
        Node temp = head;
        while (temp != null) {
            System.out.print(temp.data + " -> ");
            temp = temp.next;
        }
        System.out.println("null");
    }
}