在我们的四则运算表达式里面我们可以利用继承实行从一元到二元操作符的表示，但它实质上会干扰测试。

In our arithmetic expressions we could have used inheritance to get from a unary to a binary operator node, but that would substantially violate the test.

youdao

在我们的四则运算表达式里面我们可以利用继承实行从一元到二元操作符的表示，但它实质上会干扰测试。

In our arithmetic expressions we could have used inheritance to get from a unary to a binary operator node, but that would substantially violate the test.

youdao