What are the differences between a pointer variable and a reference variable in C++?

問題：

I know references are syntactic sugar, so code is easier to read and write.我知道引用是語法糖，所以代碼更容易閱讀和編寫。

But what is the difference between a pointer variable and a reference variable?但是指針變量和引用變量有什麼區別呢？

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解決方案：

參考一： https://en.stackoom.com/question/Ex9參考二： https://stackoom.com/question/Ex9