packageTutorial18;importjava.util.ArrayList;importjava.util.Collections;importjava.util.Comparator;importjava.util.Iterator;importjava.util.List;//定义学生类classStudent{privateStringname;privateStringstudentId;privatein

```mermaidclassDiagramclassExpression{<<interface>>+interpret()String}classDirection{-Stringdirection+interpret()String}classAction{-Stringaction+inter