Leetcode Remove Duplicates from Sorted List

Given a sorted linked list, delete all duplicates such that each element appear only once.

For example,
Given 1->1->2, return 1->2.
Given 1->1->2->3->3, return 1->2->3.

Difficulty: Easy

/** * Definition for singly-linked list. * public class ListNode { *     int val; *     ListNode next; *     ListNode(int x) { val = x; } * } */public class Solution {    public ListNode deleteDuplicates(ListNode head) {        if(head == null) return null;        ListNode curr = head;        while(curr.next != null){            if(curr.val == curr.next.val){                curr.next = curr.next.next;            }            else{                curr = curr.next;            }        }        return head;    }}