from collections import deque
class TreeNode:
def __init__(self, val=0, left=None, right=None):
self.val = val
self.left = left
self.right = right
def treenode_build(vals):
if not vals:
return None
root = TreeNode(vals[0])
q, i = deque([root]), 1
while q and i < len(vals):
curr = q.popleft()
if vals[i] is not None:
curr.left = TreeNode(vals[i])
q.append(curr.left)
i += 1
if i < len(vals) and vals[i] is not None:
curr.right = TreeNode(vals[i])
q.append(curr.right)
i += 1
return root
def treenode_print(root):
if not root:
return
q, res = deque([root]), []
while q:
curr = q.popleft()
if curr:
res.append(str(curr.val))
q.append(curr.left)
q.append(curr.right)
else:
res.append("null")
while res and res[-1] == "null":
res.pop()
print(res)
class ListNode:
def __init__(self, val=0, next=None):
self.val = val
self.next = next
def listnode_build(vals):
if not vals or vals[0] is None:
return None
head = ListNode(vals[0])
curr = head
for i in vals[1:]:
curr.next = ListNode(i)
curr = curr.next
return head
def listnode_print(head):
if not head:
return
res, curr = [], head
while curr:
res.append(str(curr.val))
curr = curr.next
print(res)
