(nil, 14)
root = insertNode(root, 7)
root = insertNode(root, 1)
root = insertNode(root, 2...)
root = insertNode(root, 3)
root = insertNode(root, 4)
root = insertNode(root, 5)
root...= insertNode(root, 6)
root = insertNode(root, 8)
root = insertNode(root, 9)
root = insertNode...(root, 10)
root = insertNode(root, 11)
root = insertNode(root, 12)
root = insertNode(root..., 13)
root = insertNode(root, 15)
// Insert key 36
root = insertNode(root, 36)
fmt.Println