fix:移除链表元素

02-链表/problem_solving_07.py

+"""
+移除链表元素
+"""
+from typing import Optional
+
+
+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]:
+        """
+        链表的合适是操作2个节点,前驱和后继
+        :param head:
+        :param val:
+        :return:
+        """
+        # 处理头部节点
+        while head and head.val == val:
+            head = head.next
+        # 处理非头部
+        cur = head
+        while cur and cur.next:
+            if cur.next.val == val:
+                cur.next = cur.next.next
+            else:
+                cur = cur.next
+        return head
+
+
+if __name__ == '__main__':
+    # 1, 2, 6, 3, 4, 5, 6
+    l1 = ListNode(7)
+    l1.next = ListNode(7)
+    l1.next.next = ListNode(7)
+    l1.next.next.next = ListNode(7)
+    # l1.next.next.next.next = ListNode(7)
+    # l1.next.next.next.next.next = ListNode(7)
+    # l1.next.next.next.next.next.next = ListNode(7)
+    # l2 = ListNode(5)
+    # l2.next = ListNode(6)
+    # l2.next.next = ListNode(1)
+    # l2.next.next.next = ListNode(8)
+    # l2.next.next.next.next = ListNode(4)
+    # l2.next.next.next.next.next = ListNode(5)
+    result = Solution().removeElements(l1, 7)
+    print(result)