import java.util.List;

import java.util.Scanner;

class Subject {

public String mamh;

public String tenmh;

public int sotin;

}

class Student {

public String masv;

public String ten;

public int somh;

}

class Invoice {

public Student a;

public List<Subject> b;

public String quyDinh;

public int hocPhi;

public int tongTin;

public int tongThu;

}

class PaymentController {

public Invoice getInvoice() {

Scanner input = new Scanner(System.in);

Invoice c = new Invoice();

c.a.masv = input.nextLine();

c.a.ten = input.nextLine();

c.a.somh = input.nextLine();

for (int i = 1; i <= c.a.somh; i++) {

Subject subject = new Subject();

subject.mamh = input.nextLine();

subject.tenmh = input.nextLine();

subject.sotin = input.nextInt();

c.b.add(subject);

c.tongTin = c.tongTin + subject.sotin;

}

c.quyDinh = input.nextLine();

c.hocPhi = input.nextInt();

c.tongThu = c.tongTin * c.hocPhi;

input.close();

return c;

}

}

public class dongtien {

public static void main(String[] args) {

PaymentController pc = new PaymentController();

// Output for test

Invoice invoice = pc.getInvoice();

// InvoiceView.show(invoice);

}

}