#include<bits/stdc++.h>
#include<vector>

using namespace std;

int getCnt(vector<string>& proxy, vector<string>& server, int m){
    // index表示每次遍历 serve 时的起始下标
    int index = 0, count = 0;
    while(index < m){
        int maxn = 0;//代表 index 右移的最大距离
        // 遍历代理服务器
        for(string ip : proxy){
            int j = index;
            while(j < m && ip != server[j]) j ++;
            maxn = max(maxn, j - index);
        }
        if(maxn == 0) return -1;
        count ++;
        index += maxn;
    }
    return count - 1;
}

int main(){
    int n, m;
    while(cin >> n){
        vector<string> proxy(n);
        for(int i = 0; i < n; i ++){
            cin >> proxy[i];
        }
        cin >> m;
        vector<string> server(m);
        for(int i = 0; i < m; i ++)
            cin >> server[i];
        cout << getCnt(proxy, server, m);
    }
}