里氏替换原则是面向对象编程中的一个基本概念,确保派生类可以替代其基类使用,而不会改变程序的正确性。
At an early age I learned that people make mistakes, and you have to decide if their mistakes are bigger than your love for them.
世界会打击每一个人,但经历过后,许多人会在受伤的地方变得更坚强。
Always think big and don't listen to people who tell you it can't be done.