83. Remove Duplicates from Sorted List

class Solution {
    public ListNode deleteDuplicates(ListNode head) {
        if (head == null) {
            return head;
        }
        ListNode current = head;
        while (current != null) {
            ListNode next = findNext(current);
            current.next = next;
            current = next;
        }
        return head;
    }

    private static ListNode findNext(ListNode node) {
        ListNode next = node.next;
        while (next != null && node.val == next.val) {
            next = next.next;
        }
        return next;
    }
}