#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
#define fi first
#define se second
#define mp make_pair
#define fastIO ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
const int N = 250111;
vector<int> T[N];
int idx[N];
int mod[N];
vector<int> ord[N];
vector<int> dp[N];
vector<bool> vis[N];
bool outit[N];
int qash[N];
struct item{
ll dist;
int p;
int q;
bool operator<(const item &pq) const {
return pq.dist < dist;
}
};
int main(){
fastIO;
int n, m;
cin >> n >> m;
int u, v;
for(int i = 1; i <= m ; i ++ ){
cin >> u >> v;
T[u].push_back(v);
T[v].push_back(u);
}
int k;
cin >> k;
int sz;
for(int iq = 1; iq <= k; iq ++ ){
cin >> sz;
mod[iq] = sz ;
for(int i = 1; i <= sz ; i ++ ){
cin >> u;
qash[u] = i - 1;
idx[u] = iq;
ord[iq].push_back(u);
}
}
for(int i = 1; i <= n; i ++ ){
if(idx[i] == 0){
dp[i].resize(1,(int)1e9);
vis[i].resize(1, false);
}
else{
dp[i].resize(mod[idx[i]],(int)1e9);
vis[i].resize(mod[idx[i]],false);
}
}
dp[1][0] = 0;
priority_queue<item> pq;
pq.push({0, 1, 0});
int node;
int dis;
int res;
int nex;
int ix;
int ban0, ban1;
while(!pq.empty()){
node = pq.top().p;
res = pq.top().q;
dis = pq.top().dist;
pq.pop();
if(vis[node][res]) continue;
vis[node][res]=true;
if(idx[node] == 0){
for(auto x : T[node]){
if(idx[x] == 0){
if(dp[x][0] > dis + 1){
dp[x][0] = dis + 1;
pq.push({dis + 1, x, 0});
}
}
else{
for(int j = 1; j <= mod[idx[x]]; j ++ ){
nex = (dis + j) % mod[idx[x]];
if(ord[idx[x]][nex] != x){
if(dp[x][nex] > dis + j){
dp[x][nex] = dis + j;
pq.push({dis + j, x, nex});
}
}
}
}
}
}
else{
if(!outit[node]){
outit[node]=true;
for(auto x : T[node]){
if(idx[x] == 0){
if(dp[x][0] > dis + 1){
dp[x][0] = dis + 1;
pq.push({dis + 1, x, 0});
}
}
}
}
ix = qash[node];
if(node != ord[idx[node]][(res + 1) % mod[idx[node]]]){
if(dp[node][(res + 1) % mod[idx[node]]] > dis + 1){
dp[node][(res + 1) % mod[idx[node]]] = dis + 1;
pq.push({dis + 1, node, (res + 1) % mod[idx[node]]});
}
}
nex = ord[idx[node]][(ix + 1) % mod[idx[node]]];
if(dp[nex][(res + 1) % mod[idx[node]]] > dis + 1){
dp[nex][(res + 1) % mod[idx[node]]] = dis + 1;
pq.push({dis + 1, nex, (res + 1) % mod[idx[node]]});
}
ban0 = ord[idx[node]][res];
ban1 = ord[idx[node]][(res + 1) % mod[idx[node]]];
nex = ord[idx[node]][(ix - 1 + mod[idx[node]]) % mod[idx[node]]];
if(nex != ban0 && nex != ban1 && dp[nex][(res + 1) % mod[idx[node]]] > dis + 1){
dp[nex][(res + 1) % mod[idx[node]]] = dis + 1;
pq.push({dis + 1, nex, (res + 1) % mod[idx[node]]});
}
}
}
if(dp[n][0] > (int)1e8)
cout << "impossible\n";
else
cout << dp[n][0] << "\n";
return 0;
}
