A26931. 下面代码实现一个二叉排序树的插入函数（没有相同的数值），横线处应填入（ ）。class TreeNode: def __init__(self, val=0, left=None, right=None): self.val = val self.left = left self.right = right def insert(root, key): if root is None: retu…

if key < root.val:
	root.left = insert(root.left, key)
elif key > root.val:
	root.right = insert(root.right, key)

if key > root.val:
	root.left = insert(root.left, key)
elif key > root.val:
	root.right = insert(root.right, key)

if key < root.val:
	root.left = insert(root.left, key)
elif key >= root.val:
	root.right = insert(root.left, key)

if key < root.val:
	root.left = insert(root.right, key)
elif key > root.val:
	root.right = insert(root.left, key)