Delete duplicate-value nodes from a sorted linked list

Duplicate-Value nodes removel in linked list java code

Expalnation 
input:- 1->2->2->3->3->3->4->null
output:-1->2->3->4->null

############################JAVA CODE######################################

    // Complete the removeDuplicates function below.

    /*
     * For your reference:
     *
     * SinglyLinkedListNode {
     *     int data;
     *     SinglyLinkedListNode next;
     * }
     *
     */
    static SinglyLinkedListNode removeDuplicates(SinglyLinkedListNode head) {
           SinglyLinkedListNode curr=head;
           //SinglyLinkedListNode prev=null;
           while(curr!=null){
               SinglyLinkedListNode prev=curr;
               while(prev!=null && prev.data==curr.data){
                   prev=prev.next;
                 }
                curr.next=prev;
               curr=curr.next;
           }
          return head;

    }