5.26打卡

#include <bits/stdc++.h>
using namespace std;
class ExamInfo
{
    public:
    ExamInfo(string name,char grade)
    :name(name),mode(GRADE),grade(grade){}
    ExamInfo(string name,bool pass)
    :name(name),mode(PASS),pass(pass){}
    ExamInfo(string name,int percent)
    :name(name),mode(PERCENTAGE),percent(percent){}
    void show();
    private:
        string name;
        enum{
            GRADE,
            PASS,
            PERCENTAGE,
        }mode;
        union{
            char grade;
            bool pass;
            int percent;
        };
};
void ExamInfo::show(){
    cout<<name<<": ";
    switch(mode)
    {
        case GRADE:cout<<grade;
        break;
        case PASS:
            cout<<(pass?"PASS":"FAIL");
            break;
        case PERCENTAGE:
        cout<<percent;
        break; 
     } 
     cout<<endl;
}
int main()
{
    ExamInfo course1("English",'B');
    ExamInfo course2("Calculus",true);
    ExamInfo course3("C++Programming",85);
    course1.show();
    course2.show();
    course3.show();
    return 0;
}