package?shili;import?java.util.ArrayList;import?java.util.List;import?java.util.Scanner;public?class?StudentTest?{public?List<Course>?a;public?StudentTest()?{	this.a=new?ArrayList<Course>();}public?void?addCourse()?{	Course?cr1=new?Course("1","米飯");	Course?cr2=new?Course("2","包子");	Course?cr3=new?Course("3","餅");	Course?cr4=new?Course("4","餃子");	Course?cr5=new?Course("5","饅頭");	Course?cr6=new?Course("6","壽司");	Course?cr7=new?Course("7","雞腿");	a.add(cr1);	a.add(cr2);	a.add(cr3);	a.add(cr4);	a.add(cr5);	a.add(cr6);	a.add(cr7);}public?void?forec()?{	for(Object?k:a)?{		Course?cr=(Course)?k;		System.out.println(cr.id+cr.name);	}}public?static?void?main(String[]?args)?{			StudentTest?xc=new?StudentTest();	System.out.println("本餐廳有以下主食：");	xc.addCourse();	xc.forec();	Student?student=new?Student("1","小明");		System.out.println("請"+student.name+"選餐：");	Scanner?xh=new?Scanner(System.in);		for(int?i=0;i<3;i++)?{		System.out.println("請輸入食物序號：");		int?one=xh.nextInt();		for(Course?cr:xc.a)?{						if(cr.id.equals(xh))?{				student.courses.add(cr);							}		}	}xc.f(student);}public?void?f(Student?student)?{	for(Course?cr:student.courses)?{		System.out.println(cr.id+cr.name);	}}			}

這里的Course類和Student類都和視頻里的一樣，各位大佬幫我看一下為什么不會執行最后的f（）；方法