#include <bits/stdc++.h>
using namespace std;
#define FOR(i,k,n) for(int i = (int)(k); i < (int)(n); i++)
#define REP(i,n) FOR(i,0,n)
#define ALL(a) a.begin(), a.end()
#define MS(m,v) memset(m,v,sizeof(m))
#define D10 fixed<<setprecision(10)
typedef long long ll;
typedef long double ld;
typedef vector<int> vi;
typedef vector<string> vs;
typedef pair<int, int> pii;
const int MOD = 1000000007;
const int INF = MOD + 1;
const ld EPS = 1e-12;
template<class T> T &chmin(T &a, const T &b) { return a = min(a, b); }
template<class T> T &chmax(T &a, const T &b) { return a = max(a, b); }

/*--------------------template--------------------*/
typedef int Weight;
struct Edge
{
	int from, to; Weight cost;
	bool operator < (const Edge& e) const { return cost < e.cost; }
	bool operator > (const Edge& e) const { return cost > e.cost; }
};
typedef vector<Edge> Edges;
typedef vector<Edges> Graph;
typedef vector<Weight> Array;
typedef vector<Array> Matrix;
void add_edge(Graph &g, int from, int to, Weight cost)
{
	g[from].push_back(Edge{ from, to, cost });
}

vs input(string& s)
{
	int t = s.find('-');
	string l = s.substr(0, t);
	string r = s.substr(t + 1);
	vs res;
	res.push_back(l); res.push_back(r);
	return res;
}

int main()
{
	int n;
	while (cin >> n, n)
	{
		vector<vs> v(n);
		map<string, int> mp;
		REP(i, n)
		{
			string s; cin >> s;
			v[i] = input(s);
		}
		int p = 0;
		REP(i, n)REP(j, 2)
		{
			string tmp = v[i][j];
			if (mp.count(tmp)) continue;
			mp[tmp] = p;
			p++;
		}
		cout << p << endl;
		Graph g(p);
		Matrix dist(p, Array(p));
		REP(i, n)
		{
			int l = mp[v[i][0]], r = mp[v[i][1]];
			add_edge(g, l, r, 1);
			add_edge(g, r, l, 1);
			dist[r][l] = 1;
		}
		vector<pii> same;
		REP(i, p)REP(j, i)
		{
			bool f1 = false, f2 = true;
			REP(k, p)
			{
				if ((dist[i][k] || dist[k][i]) && (dist[j][k] || dist[k][j])) f1 = true;
				if ((dist[i][k] && dist[k][j]) || (dist[k][i] && dist[j][k])) f2 = false;
			}
			if (f1&&f2) same.emplace_back(i, j);
		}
		for (auto i : same)
		{
			dist[i.first][i.second] = 1;
			dist[i.second][i.first] = 1;
		}
		REP(k, p)REP(i, p)REP(j, p)
		{
			if (dist[i][k] && dist[k][j]) dist[i][j] = 1;
		}
		vi color(p);
		int col = 1;
		REP(i, p)
		{
			if (color[i]) continue;
			queue<int> que;
			que.push(i);
			int c = col, d = -col;
			color[i] = c;
			while (que.size())
			{
				int t = que.front();
				que.pop();
				int nx = (color[t] == c ? d : c);
				REP(j, g[t].size())
				{
					if (color[g[t][j].to]) continue;
					color[g[t][j].to] = nx;
					que.push(g[t][j].to);
				}
			}
			col++;
		}
		int q;
		cin >> q;
		REP(i, q)
		{
			string s; cin >> s;
			vs t = input(s);
			if (!mp.count(t[0]) || !mp.count(t[1]))
			{
				puts("NO");
				continue;
			}
			int l = mp[t[0]], r = mp[t[1]];
			if (color[l] == -color[r] && dist[r][l])
			{
				puts("YES");
			}
			else
			{
				puts("NO");
			}
		}
	}
	return 0;
}