Remove Duplicates from Sorted List

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

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Example
Given 1->1->2, return 1->2.
Given 1->1->2->3->3, return 1->2->3.

/**
 * Definition for ListNode
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode(int x) {
 *         val = x;
 *         next = null;
 *     }
 * }
 */
public class Solution {
    /**
     * @param ListNode head is the head of the linked list
     * @return: ListNode head of linked list
     */
    public static ListNode deleteDuplicates(ListNode head) { 
        // write your code here
        if(head==null) return head;
        ListNode node =head;
        while(node.next!=null){
            if(node.val==node.next.val){
                node.next = node.next.next;
            }
            else 
            node=node.next;
        }
        return head;

    }  
}