如果这是家庭作业，请确保建议您解释代码。更好的方法是编写代码，卡住，在这里寻求帮助，而不是在没有自己编写代码的情况下寻求帮助。这样你就可以边做边学。

If this is a homework assignment make sure whatever is suggested you can explain the code. A better way to go is write code, get stuck, ask here for assistance rather than asking for help w/o writing code yourself. This way you are learning by doing.