#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for(long long i=0;i<(long long)(n);i++)
#define REP(i,k,n) for(long long i=k;i<(long long)(n);i++)
#define pb emplace_back
#define lb(v,k) (lower_bound(all(v),(k))-v.begin())
#define ub(v,k) (upper_bound(all(v),(k))-v.begin())
#define fi first
#define se second
#define pi M_PI
#define PQ(T) priority_queue<T>
#define SPQ(T) priority_queue<T,vector<T>,greater<T>>
#define dame(a) {out(a);return 0;}
#define decimal cout<<fixed<<setprecision(15);
#define all(a) a.begin(),a.end()
#define rsort(a) {sort(all(a));reverse(all(a));}
#define dupli(a) {sort(all(a));a.erase(unique(all(a)),a.end());}
typedef long long ll;
typedef pair<ll,ll> P;
typedef tuple<ll,ll,ll> PP;
typedef tuple<ll,ll,ll,ll> PPP;
using vi=vector<ll>;
using vvi=vector<vi>;
using vvvi=vector<vvi>;
using vvvvi=vector<vvvi>;
using vp=vector<P>;
using vvp=vector<vp>;
using vb=vector<bool>;
using vvb=vector<vb>;
const ll inf=1001001001001001001;
const ll INF=1001001001;
const ll mod=998244353;
const double eps=1e-10;
template<class T> bool chmin(T&a,T b){if(a>b){a=b;return true;}return false;}
template<class T> bool chmax(T&a,T b){if(a<b){a=b;return true;}return false;}
template<class T> void out(T a){cout<<a<<'\n';}
template<class T> void outp(T a){cout<<'('<<a.fi<<','<<a.se<<')'<<'\n';}
template<class T> void outvp(T v){rep(i,v.size())cout<<'('<<v[i].fi<<','<<v[i].se<<')';cout<<'\n';}
template<class T> void outvvp(T v){rep(i,v.size())outvp(v[i]);}
template<class T> void outv(T v){rep(i,v.size()){if(i)cout<<' ';cout<<v[i];}cout<<'\n';}
template<class T> void outvv(T v){rep(i,v.size())outv(v[i]);}
template<class T> bool isin(T x,T l,T r){return (l)<=(x)&&(x)<=(r);}
template<class T> void yesno(T b){if(b)out("yes");else out("no");}
template<class T> void YesNo(T b){if(b)out("Yes");else out("No");}
template<class T> void YESNO(T b){if(b)out("YES");else out("NO");}
template<class T> void outset(T s){auto itr=s.begin();while(itr!=s.end()){if(itr!=s.begin())cout<<' ';cout<<*itr;itr++;}cout<<'\n';}
void outs(ll a,ll b){if(a>=inf-100)out(b);else out(a);}
ll gcd(ll a,ll b){if(b==0)return a;return gcd(b,a%b);}
ll modpow(ll a,ll b){ll res=1;a%=mod;while(b){if(b&1)res=res*a%mod;a=a*a%mod;b>>=1;}return res;}
int main(){
cin.tie(0);
ios::sync_with_stdio(false);
ll n,m;cin>>n>>m;
map<P,ll> edges;
vvp g(n);
rep(i,m){
ll a,b;cin>>a>>b;a--;b--;
g[a].pb(b,i);g[b].pb(a,i);
edges[P(min(a,b),max(a,b))]=i;
}
ll k;cin>>k;
vi len(n,1),ngv(n,-1),nge(m,-1);
vvp sp(n);
rep(j,k){
ll l;cin>>l;
vi v(l);
rep(i,l){
cin>>v[i];v[i]--;
}
rep(i,l){
ngv[v[i]]=i;len[v[i]]=l;
ll id=edges[P(min(v[i],v[(i+1)%l]),max(v[i],v[(i+1)%l]))];
nge[id]=i;
sp[v[i]].pb(v[(i+1)%l],id);
sp[v[(i+1)%l]].pb(v[i],id);
}
}
vb ok(n,false);
rep(i,n)for(auto x:g[i])if(ngv[x.fi]==-1)ok[i]=true;
vvi dis(n);
rep(i,n)dis[i]=vi(len[i],inf);
dis[0][0]=0;
vi dis2(n,inf);
queue<P> que,que2;
que.emplace(0,0);
while(!pq.empty()){
while(que2.size()&&que2.front().fi==que.front().fi){
que.push(que2.front());que2.pop();
}
ll i=que.front().fi,j=que.front().se,cost=dis[i][j];que.pop();
if(chmin(dis2[i],cost)){
for(auto x:g[i]){
bool f=true;
for(auto y:sp[i])if(x==y)f=false;
if(!f)continue;
ll nc=cost+1;
if(ngv[x.fi]==nc%len[x.fi])nc++;
if(chmin(dis[x.fi][nc%len[x.fi]],nc))que.emplace(x.fi,nc%len[x.fi]);
}
}
for(auto x:sp[i]){
if(nge[x.se]==cost%len[x.fi])continue;
ll nc=cost+1;
if(ngv[x.fi]==nc%len[x.fi])continue;
if(chmin(dis[x.fi][nc%len[x.fi]],nc))que.emplace(x.fi,nc%len[x.fi]);
}
if(ngv[i]==(cost+1)%len[i]){
if(ok[i]&&chmin(dis[i][(cost+2)%len[i]],cost+2))que.emplace(i,(cost+2)%len[i]);
}
else if(chmin(dis[i][(cost+1)%len[i]],cost+1))que2.emplace(i,(cost+1)%len[i]);
}
ll ans=inf;
for(ll x:dis[n-1])chmin(ans,x);
if(ans==inf)out("impossible");
else out(ans);
}
Compilation message
watchmen.cpp: In function 'int main()':
watchmen.cpp:87:12: error: 'pq' was not declared in this scope; did you mean 'pb'?
87 | while(!pq.empty()){
| ^~
| pb
