include <bits/stdc++.h>

using namespace std; const int MAXN = 30, MAXM = 610; int ind[MAXN], h[MAXN], ans[MAXN], n, m, idx; bool st[30][30];

struct CharRec { //存储读入的限制条件中的对应的顶点编号

int u, v;

} e[MAXN];

struct rec {

int to, nxt;

} edge[MAXM];

queueq;

void add(int x, int y) {

edge[idx].to = y;
edge[idx].nxt = h[x];
h[x] = idx++;

}

void init() {

char x, y, z;
cin >> n >> m;
for (int i = 1; i <= m; i++) {
	cin >> x >> y >> z;
	if (st[x - 'A' + 1][z - 'A' + 1])
		continue;
	st[x - 'A' + 1][z - 'A' + 1] = 1;
	e[i].u = x - 'A' + 1;
	e[i].v = z - 'A' + 1;
	add(e[i].u, e[i].v);
}

}

int topsort() {

int num = 0, flag = 0, temp = 0; //num记数，flag讨论三种情况，temp临时
for (int i = 1; i <= n; i++) {
	if (ind[i] == 0) {
		q.push(i);
		num++;
	}
}
if (num > 1)
	flag = 1; //用1来表示入度为0的点不止一个。
while (!q.empty()) {
	num = 0;
	for (int i = h[q.front()]; i != -1; i = edge[i].nxt) {
		int v = edge[i].to;
		ind[v]--;
		if (ind[v] == 0) {
			q.push(v);
			num++;
		}
	}
	if (num > 1)
		flag = 1; //同时产生的入度为0顶点不止一个。
	ans[++temp] = q.front();
	q.pop();
}
if (temp < n)
	return -1;//存在环  返回-1
else if (flag == 1)
	return 0;
else
	return 1;

}

void work() {

memset(h, -1, sizeof h);
for (int i = 1; i <= m; i++) {
	memset(ind, 0, sizeof ind);
	memset(ans, 0, sizeof ans);
	add(e[i].u, e[i].v);
	for (int j = 1; j <= i; j++)
		ind[e[j].v]++;
	int f = topsort();
	if (f == -1) { //存在环
		cout << "Inconsistency found after " << i << " relations." << endl;
		return;
	} else if (f == 1) { //确定了拓扑排序，输出
		cout << "Sorted sequence determined after " << i << " relations: ";
		for (int j = 1; j <= n; j++)
			cout << char(ans[j] + 'A' - 1);
		cout << "." << endl;
		return;
	} else
		continue; //继续增加一条边进行判断
}
cout << "Sorted sequence cannot be determined." << endl;
return;

}

int main() {

init();
work();
return 0;

}