#include <bits/stdc++.h>
using namespace std;
string a, b, huan[8][2];
int n = 1;

struct node {
	string str;
	int num;
};

int bfs() {
	queue<node> q;
	node now, neww;
	now.num = 0;
	now.str = a;
	int x;
	string y, z;
	q.push(now);
	while (!q.empty()) {
		now = q.front();
		if (now.str == b || now.num > 10) {
			break;
		}
		q.pop();
		for (int i = 1; i <= n; i++) {
			z = now.str;
			while (1) {
				y = now.str;
				x = z.find(huan[i][0]);
				if (x == -1) {
					break;
				}
				y.replace(x, huan[i][0].size(), huan[i][1]);
				neww.num = now.num + 1;
				neww.str = y;
				q.push(neww);
				z[x] = '~';
			}
		}
	}
	if (now.num <= 10 && !q.empty()) {
		return now.num;
	}
	return -1;
}

int main() {
	cin >> a >> b;
	while (cin >> huan[n][0] >> huan[n][1]) {
		n++;
	}
	n--;
	if (n == 0 && a != b) {
		cout << "NO ANSWER!";
		return 0;
	}
	if (a == b) {
		cout << 0;
		return 0;
	}
	int x = bfs();
	if (x >= 0) {
		cout << x;
	} else {
		cout << "NO ANSWER!";
	}
	return 0;
}

应该是“爆队列长度”了吧......