이용권마다 다른 차감량

#include <iostream>
#include <vector>
using namespace std;

class Pass {
protected:
    int unit;
public:
    Pass(int value) : unit(value) {}
    virtual int charge(int uses) const = 0;
    virtual ~Pass() {}
};
class SinglePass : public Pass {
public:
    SinglePass(int value) : Pass(value) {}
    int charge(int uses) const override {
        return /*@blank1@*/;
    }
};
class BundlePass : public Pass {
    int bundle;
public:
    BundlePass(int value, int size) : Pass(value), bundle(size) {}
    int charge(int uses) const override {
        int count = /*@blank2@*/;
        return count * unit;
    }
};
int solution(vector<vector<int>> passes) {
    int total = 0;
    for (vector<int> row : passes) {
        if (row[0] == 0) {
            SinglePass pass(row[1]);
            total += pass.charge(row[3]);
        } else {
            BundlePass pass(row[1], row[2]);
            total += pass.charge(row[3]);
        }
    }
    return total;
}
int main() {
    int n;
    cin >> n;
    vector<vector<int>> passes(n, vector<int>(4));
    for (int i = 0; i < n; ++i)
        for (int j = 0; j < 4; ++j) cin >> passes[i][j];
    cout << solution(passes) << '\n';
}