c++继承与多态问题

class C {
public:
    char getClass();
     int getN();
};
class A :public C {
public:
    A(int n) {
        this->n = n;
    }
    char getClass() {
        return 'A';
    }
    int getN() {
        return n;
    }
private:
    int n;
};
class B :public C {
public:
    B(int n)  {
        this->n = n;
    }
    char getClass() {
        return 'B';
    }
    int getN() {
        return n;
    }
private:
    int n;
};
C *a[100];
void PrintInfo(C* a) {
    cout << a->getClass() << " " << a->getN();
}

int main() {
    int t;
    cin >> t;
    while (t--) {
        int n;
        cin >> n;
        for (int i = 0; i < n; ++i) {
            char c;
            int k;
            cin >> c >> k;
            if (c == 'A')
                a[i] = new A(k);
            else
                a[i] = new B(k);
        }
        cout << n << endl;
        for (int i = 0; i < n; ++i)
            PrintInfo(a[i]);
        cout << "****" << endl;
    }
}

A，B继承C类，main函数不能动，这个PrintInfo函数有什么问题吗，要怎么解决

没实现c类函数，继承间发生多太行为需要virtual关键字，纯虚函数应该= 0