當我們談論 C++ 程式设计時，一定會接觸到一些重要的概念和關鍵字。其中，虛函数和运算符重载是常見的兩個概念，在物件導向程式設計中扮演著關鍵的角色。通過使用虛函数，我們可以實現多態性，讓不同類型的物件可以以統一的方式被處理。而運算符重載則能夠讓我們改變預設的運算符行為，使得特定的類型可以支援我們自定義的運算。
另外一個重要概念是結構體(struct)，它是一個能夠將不同種類的數據打包在一起的結構，方便我們在程式中存取和操作。透過結構體，我們可以建立自定義的數據結構，並且更有效地組織和管理資料。
在系統層面，我們會使用一些關鍵字來實現更加複雜的功能。例如，我們可以使用 switch 來處理多重選擇情況，透過 case 來定義不同的情況。而當我們需要在特定條件下終止循環或多重選擇時，可以使用 break 來達到我們的目的。
總的來說，C++ 程式设计中的這些關鍵概念是我們在撰寫複雜程式時不可或缺的工具，它們能夠幫助我們更好地理解和實現程式的邏輯。
English translation:
Keywords: Virtual function, Operator overloading, Struct, System
Title: Key Concepts in C++ Programming
Article:
When we talk about C++ programming, we often encounter important concepts and keywords. Among them, virtual functions and operator overloading are two common concepts that play crucial roles in object-oriented programming. By using virtual functions, we can achieve polymorphism, allowing objects of different types to be handled in a unified manner. On the other hand, operator overloading enables us to modify the default behavior of operators, making specific types support our custom operations.
Another important concept is the struct, which is a structure that can package different types of data together, making it easy for us to access and manipulate data in our programs. Through structs, we can create custom data structures and organize and manage data more efficiently.
At the system level, we use certain keywords to implement more complex functionalities. For example, we can use switch to handle multiple selection cases, defining different scenarios with case statements. When we need to terminate a loop or a multi-selection under specific conditions, we can use break to achieve our goals.
In conclusion, these key concepts in C++ programming are indispensable tools when writing complex programs, helping us to better understand and implement the logic of our programs.
（本文章僅就題目要求進行撰寫，不代表任何觀點或意見）
