#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define pb emplace_back
#define AI(i) begin(i), end(i)
template<class T> bool chmin(T &a, T b) { return b < a && (a = b, true); }
template<class T> bool chmax(T &a, T b) { return a < b && (a = b, true); }
#ifdef KEV
#define DE(args...) kout("[ " + string(#args) + " ] = ", args)
void kout() { cerr << endl; }
template<class T, class ...U> void kout(T a, U ...b) { cerr << a << ' ', kout(b...); }
void debug(auto l, auto r) { while (l != r) cerr << *l << " \n"[next(l)==r], ++l; }
#else
#define DE(...) 0
#define debug(...) 0
#endif
using t3 = pair<ll,int>;
const int MAX_N = 300010, MAX_K = 2800, hol = 100;
const ll inf = 1ll << 55;
int n, m;
vector<int> edge[MAX_N], cyc[MAX_N];
vector<ll> dp[MAX_N];
int cid[MAX_N], csz[MAX_N], cpos[MAX_N];
int32_t main() {
ios_base::sync_with_stdio(0), cin.tie(0);
cin >> n >> m;
for (int a, b, i = 0;i < m;++i) {
cin >> a >> b;
edge[a].pb(b);
edge[b].pb(a);
}
for (int i = 1;i <= n;++i) {
dp[i].resize(1, inf);
csz[i] = 1;
}
int K;
cin >> K;
for (int i = 1;i <= K;++i) {
int len;
cin >> len;
cyc[i].resize(len);
int c = 0;
for (int &u : cyc[i]) {
cin >> u;
cid[u] = i;
csz[u] = len;
cpos[u] = c++;
dp[u].resize(len, inf);
DE(u, cpos[u], len);
}
}
//priority_queue<t3, vector<t3>, greater<t3>> q;
//queue<pair<ll,int>> q;
vector<vector<int>> q;
auto putin = [&](int d, int x) {
if (q.size() < d + 1) q.resize(d + 1);
q[d].pb(x);
};
auto upd = [&](int x, ll d) {
if (chmin(dp[x][d % csz[x]], d))
putin(d, x);
};
upd(1, 0);
// shortest path
// now there are no two cycle being connected
// check if at x, time is d can move to
auto valid = [&](int x, ll d, int u) {
if (cid[u] == 0) return true;
if (d % csz[u] == cpos[u]) return false;
if (cid[x] == 0) return true;
assert(cid[x] == cid[u]);
if (cpos[u] == (cpos[x] - 1 + csz[x]) % csz[u]) {
if (d % csz[u] == cpos[x]) return false;
}
return true;
};
for (int d = 0;d < q.size();++d) {
for (int i = 0;i < q[d].size();++i) {
int x = q[d][i];
//
// while (q.size()) {
// //auto [d, x] = q.front(); q.pop();
// auto [d, x] = q.top(); q.pop();
//if (d != dp[x][ d % csz[x] ]) continue;
if (cid[x]) {
int sz = 0;
for (int u : edge[x]) {
if (cid[u] == 0) {
upd(u, d + 1);
continue;
}
else {
if (valid(x, d + 1, u))
upd(u, d + 1);
edge[x][sz++] = u;
}
}
edge[x].resize(sz);
if (valid(x, d + 1, x))
upd(x, d + 1);
}
else {
int mxc = hol;
for (int u : edge[x]) {
if (cid[u] == 0) {
upd(u, d + 1);
continue;
}
else {
if (valid(x, d + 1, u))
upd(u, d + 1);
ll t = d + 1, m = t % csz[u];
if (m != cpos[u]) {
ll f = cpos[u] - m;
if (f < 0) f += csz[u];
t += f;
}
++t;
if (valid(x, t, u))
upd(u, t);
}
}
}
}
vector<int>().swap(q[d]);
}
//
ll res = inf;
for (auto v : dp[n]) chmin(res, v);
if (res == inf) cout << "impossible\n";
else cout << res << '\n';
}
