回複：my interview questions

1. Destructor is for releasing resource after the object completes its useful lifetime. To ensure all resources are released completely, the programmer should ensure that the processing will not be interrupted in any situation.

2. Static variable are class level variable shared by all instances of the class, the memory of a static variable is allocated and initialized at compiling time. At run time, the instatiation of instances of the class will not allocate addition memory for the static variables.