Add solution at #203.移除鏈表元素

problems/0203.移除链表元素.md

@@ -369,9 +369,31 @@ class Solution {
 ```
 
 ### Python：
+使用原鏈表操作：
+```python
+# Definition for singly-linked list.
+# class ListNode:
+#     def __init__(self, val=0, next=None):
+#         self.val = val
+#         self.next = next
+class Solution:
+	def removeElements(self, head: Optional[ListNode], val: int) -> Optional[ListNode]:    
+	    # 刪除頭節點
+	    while head is not None and head.val == val:
+	        head = head.next
+
+	    cur = head
+	    # 刪除非頭節點
+	    while head is not None and cur.next:
+	        if cur.next.val == val:
+	            cur.next = cur.next.next
+	        else:
+	            cur = cur.next
+	    return head
+```
 
+設置虛擬頭節點：
 ```python
-（版本一）虚拟头节点法
 # Definition for singly-linked list.
 # class ListNode:
 #     def __init__(self, val=0, next=None):