Search an element in a Singly Linked List

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/*Node of a single linked list of integer */
public class SinglyLinkedList {
	private static Node head; /* instance variable */

	private static class Node {
		private int data; /* we assume data integer */
		private Node next; /* Create a node with the given data and next node */

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

	/* Display the single linked list */
	public void display() {
		Node current = head;
		while (current != null) {
			System.out.print(current.data + " --> ");
			current = current.next;
		}
		System.out.println("null");
	}

	/* search element from single linked list */
	public int searchElement(int value) {
		if(head==null) {
			return -1;
		}
		int position = 0;
		Node current = head;
		while (current != null) {
			position++;
			if (current.data == value) {
				return position;
			}
			current = current.next;
		}
		return 0;
	}

	public static void main(String[] args) {
		SinglyLinkedList s = new SinglyLinkedList();
		s.head = new Node(10);
		Node second = new Node(7);
		Node third = new Node(20);
		Node fourth = new Node(80);

		s.head.next = second; // 10 --> 7
		second.next = third; // 10 -->7 --> 20
		third.next = fourth; // 10 -->7 --> 20 --> 8 -->null
		int a = s.searchElement(7);
		if(a==-1) {
			System.out.println("Empty List");
		}else if(a==0) {
			System.out.println("Element not found");
		}
		else {
			System.out.println("Element found at index " + a);
		}

	}

}