#include<iostream>
#include<string>
#include<algorithm>
#include<map>
#include<set>
#include<utility>
#include<vector>
#include<cmath>
#include<cstring>
#include<cstdio>
#include<time.h>
#define loop(i,a,b) for(int i=a;i<b;i++) 
#define rep(i,a) loop(i,0,a)
#define pb push_back
#define mp make_pair
#define all(in) in.begin(),in.end()
const double PI=acos(-1);
const double EPS=1e-10;
using namespace std;
typedef long long ll;
typedef vector<int> vi;
int main(){
	int n;
	while(cin>>n,n){
		map<string,int>in;
		rep(i,n){
			string s;int a;
			cin>>s>>a;
			in[s]=a;
		}
		cin>>n;
		rep(i,n){
			string s;
			int a;
			cin>>s>>a;
			int sum=0;
			rep(j,a){
				string tmp;
				cin>>tmp;
				sum+=in[tmp];
			}
			in[s]=min(in[s],sum);
		}
		string s;cin>>s;
		cout<<in[s]<<endl;
	}
	
}