def testBST(self):
bst = BST()
bst.add_node(10, "Apple")
self.assertEqual(bst.size(), 1)
bst.add_node(20, "Ball")
self.assertEqual(bst.size(), 2)
bst.add_node(15, "Cat")
self.assertEqual(bst.size(), 3)
bst.add_node(30, "Dog")
self.assertEqual(bst.size(), 4)
self.assertListEqual(bst.inorder_walk(), [10, 15, 20, 30])
self.assertListEqual(bst.preorder_walk(), [10, 20, 15, 30])
self.assertListEqual(bst.postorder_walk(), [15, 30, 20, 10])
from BST import BST
if __name__ == "__main__":
bst = BST()
bst.add_node("D")
bst.add_node("B")
bst.add_node("F")
bst.add_node("A")
bst.add_node("C")
bst.add_node("E")
bst.add_node("G")
print("tree initialize complete")
print("=========== Pre-Order ==========")
bst.pre_order()
print("================================")
print("=========== Post-Order ==========")
bst.post_order()
print("================================")
print("=========== In-Order ==========")
bst.in_order()
print("================================")
print("=========== level-Order ==========")
bst.level_order()
print("================================")
