t = BinaryTree()
n1 = Node(100)
n2 = Node(200)
n3 = Node(300)
n4 = Node(400)
n5 = Node(500)
n6 = Node(600)
n7 = Node(700)
n8 = Node(800)
n1.left = n2
n1.right = n3
n2.left = n4
n2.right = n5
n3.left = n6
n3.right = n7
n4.left = n8
t.root = n1
x = t.copy_tree() # 복사
print('트리 높이 =', t.height(t.root))
print('전위순회:\t', end='')
x.preorder(x.root)
print('\n중위순회:\t', end='')
x.inorder(x.root)
print('\n후위순회:\t', end='')
x.postorder(x.root)
print('\n레벨순회:\t', end='')
x.levelorder(x.root)
