#include <iostream>
#include <string>
#include <queue>
#include <set>
#include <map>

#define foreach(T,p,c) for(T p = (c).begin(); p != (c).end(); p++)

#define UNKNOWN (-1)
#define NO      (0)
#define YES     (1)

using namespace std;

struct street_t
{
	string name;
	set<string> P, C, S;	// parents, children, sibling
	int flag;
};

typedef map<string,street_t> streets_t;

void get_street(string &s0, string &s1)
{
	string s;
	cin >> s;
	int p = s.find("-");
	s0 = s.substr(0, p);
	s1 = s.substr(p + 1);
}

int main(void)
{
	int n;
	while(cin >> n) {
		if(n == 0) break;

		streets_t streets;

		for(int i = 0; i < n; i++) {
			string s0, s1;
			get_street(s0, s1);
			streets[s0].name = s0;
			streets[s1].name = s1;
			streets[s0].P.insert(s1);
			streets[s1].C.insert(s0);
		}

		foreach(streets_t::iterator, p, streets) {
			street_t *p0 = &(p->second);
			foreach(set<string>::iterator, q, p0->P) {
				street_t *p1 = &(streets[*q]);
				foreach(set<string>::iterator, r, p1->C) {
					street_t *p2 = &(streets[*r]);
					p0->S.insert(p2->name);
					p2->S.insert(p0->name);
				}
			}
			foreach(set<string>::iterator, q, p0->C) {
				street_t *p1 = &(streets[*q]);
				foreach(set<string>::iterator, r, p1->P) {
					street_t *p2 = &(streets[*r]);
					p0->S.insert(p2->name);
					p2->S.insert(p0->name);
				}
			}
		}
		foreach(streets_t::iterator, p, streets) {
			street_t *p0 = &(p->second);
			foreach(set<string>::iterator, q, p0->P) {
				street_t *p1 = &(streets[*q]);
				foreach(set<string>::iterator, r, p1->P) {
					street_t *p2 = &(streets[*r]);
					p0->S.erase(p2->name);
					p2->S.erase(p0->name);
				}
			}
		}

		cout << streets.size() << endl;

		int m;
		cin >> m;
		for(int i = 0; i < m; i++) {
			string s0, s1;
			get_street(s0, s1);

			foreach(streets_t::iterator, p, streets) {
				p->second.flag = UNKNOWN;
			}

			queue<string> q;
			streets[s0].flag = NO;
			q.push(s0);

			int flag = NO;
			while(!q.empty()) {
				string s = q.front();
				q.pop();

				if(s == s1) {
					flag = streets[s1].flag;
					break;
				}

				foreach(set<string>::iterator, p, streets[s].P) {
					if(streets[*p].flag == UNKNOWN) {
						q.push(*p);
						streets[*p].flag = 1 - streets[s].flag;
					}
				}

				foreach(set<string>::iterator, p, streets[s].S) {
					if(streets[*p].flag == UNKNOWN) {
						q.push(*p);
						streets[*p].flag = streets[s].flag;
					}
				}
			}

			cout << (flag ? "YES" : "NO") << endl;	
		}
	}

	return 0;
}