def inorder(node: TreeNode) -> str:
ret_value: str = ""
if node.get_left_child() is not None:
ret_value += "(" + inorder(node.get_left_child())
ret_value += str(node.get_root_value())
if node.get_right_child() is not None:
ret_value += inorder(node.get_right_child()) + ")"
return ret_value
def postorder(node: TreeNode) -> str:
if node is None:
return None
left = postorder(node.get_left_child())
right = postorder(node.get_right_child())
if left is not None and right is not None:
f = opers[node.get_root_value()]
return f(left, right)
else:
return node.get_root_value()
def preorder(node: TreeNode, space: int = 0):
if node is not None:
print(" " * space, node.key)
preorder(node.get_left_child(), space + 2)
preorder(node.get_right_child(), space + 2)
