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It's so hard to say goodbye to yesterday
The Liskov Substitution Principle is a fundamental concept in object-oriented programming, stating that objects of a superclass should be replaceable with objects of a subclass without affecting the correctness of the program.
The progress of science relies not only on individual wisdom but also on collective cooperation and effort.
数学研究是一次进入未知的旅程,每一次发现都为新的谜题打开了大门。
写作是从无到有创造东西的一种方式。
Man is not the creature of circumstances; circumstances are the creatures of men.