Update 083._remove_duplicates_from_sorted_list.md

083._remove_duplicates_from_sorted_list.md

@@ -9,25 +9,20 @@
 Easy
 
 
+dummy 大法
 
-
-```
+```python
 class Solution(object):
     def deleteDuplicates(self, head):
         """
         :type head: ListNode
         :rtype: ListNode
         """
-        cur = head
-        while cur:
-            if cur.next:
-                if cur.val == cur.next.val:
-                    cur.next = cur.next.next
-                else:
-                    cur = cur.next
-            # cur.next None
-            else:
-                break
-        return head
+        dummy = head
+        while head:
+            while head.next and head.next.val == head.val:
+                head.next = head.next.next    # skip duplicated node
+            head = head.next     # not duplicate of current node, move to next node
+        return dummy
                 
-```
\ No newline at end of file
+```