// editor1
import java.util.*;
class Main{
    public static void main(String[] args){
        Scanner sc=new Scanner(System.in);
        if(n<0){
            System.out.print("Invalid input");
            return;
        }
        int n=sc.nextInt();
        int ans=0;
        for(int i=0;i<n;i++){
            String s=sc.next();
            if(!(s.equals("Fruit")||s.equals("Vegetable")||s.equals("Dairy"))){
                System.out.print("Invalid input");
                return;
            }
            int q=sc.nextInt();
            if(q<0){
                System.out.print(-1);
                return;
            }
            int c=sc.nextInt();
            if(c<0){
                System.out.print(-1);
                return;
            }
            ans+=(q*c);
        }
        System.out.print(ans);
    }
}