#include<iostream>
using namespace std;
class Student {
public:
void input()
{
cout<<"输入姓名："<<endl;
cin>>name;
cout<<"输入学号："<<endl;
cin>>num;
}
void output()
{
cout<<"姓名："<<name<<endl;
cout<<"学号："<<num<<endl;
}
private:
char name[15];
int num;
};
int main()
{
Student *a[2];
for(int i=0;i<2;i++)
(*a[i]).input();
return 0;
}

有指针≠有对象

int main()
{
Student *a[2];
for(int i=0;i<2;i++)
(*a[i]).input();
return 0;
}
改为
int main()
{
Student a[2];
for(int i=0;i<2;i++)
(a[i]).input();
return 0;
}
或者
int main()
{
Student *a[2];
a[0] = new Student;
a[1] = new Student;
for(int i=0;i<2;i++)
(*a[i]).input();
return 0;
}