#include <bits/stdc++.h> using namespace std; void fast_io(){ ios::sync_with_stdio(0); cin.tie(nullptr); cout.tie(nullptr); } #define int long long #define endl '\n' #define ra(v) (v).rbegin(), (v).rend() const int N = 1e5 + 5; const int K = 300; int n, m, q, indeg[N]; vector<int> adj[N]; pair<int,int> L[N][K]; int sz[N]; int topo[N], topo_size; pair<int,int> tmp[2*K]; void merge_lists(int u, int v) { int k=0; for(int i=0;i<sz[u];i++) tmp[k++]={L[u][i].first+1, L[u][i].second}; for(int i=0;i<sz[v];i++) tmp[k++]={L[v][i].first, L[v][i].second}; sort(tmp,tmp+k,[](pair<int,int> &a,pair<int,int> &b){return a.second<b.second;}); int idx=0; for(int i=0;i<k;){ int src=tmp[i].second, best=tmp[i].first, j=i+1; while(j<k && tmp[j].second==src){best=max(best,tmp[j].first); j++;} L[v][idx++]={best, src}; i=j; if(idx==K) break; } sz[v]=idx; sort(L[v], L[v]+sz[v], greater<pair<int,int>>()); } void init_topo() { int IN[N]; for(int i=1;i<=n;i++) IN[i]=indeg[i]; queue<int> q; for(int i=1;i<=n;i++){if(IN[i]==0) q.push(i);} topo_size=0; while(!q.empty()){ int u=q.front(); q.pop(); topo[topo_size++]=u; for(int v:adj[u]){ merge_lists(u,v); if(--IN[v]==0) q.push(v); } } } signed main(){ fast_io(); cin>>n>>m>>q; for(int i=1;i<=m;i++){ int u,v; cin>>u>>v; indeg[v]++; adj[u].push_back(v); } for(int i=1;i<=n;i++){L[i][0]={0,i}; sz[i]=1;} init_topo(); while(q--){ int T,Y; cin>>T>>Y; vector<int> C(Y); unordered_set<int> bad; bad.reserve(Y*2); for(int i=0;i<Y;i++){cin>>C[i]; bad.insert(C[i]);} if(Y<=K){ bool found=0; for(int i=0;i<sz[T];i++){ if(!bad.count(L[T][i].second)){cout<<L[T][i].first<<endl; found=1; break;} } if(!found) cout<<-1<<endl; } else { int ans[N]; for(int i=1;i<=n;i++) ans[i]=0; for(int x:bad) ans[x]=-1e18; for(int i=0;i<topo_size;i++){ int u=topo[i]; for(int v:adj[u]) ans[v]=max(ans[v],ans[u]+1); } if(ans[T]<0) cout<<-1<<endl; else cout<<ans[T]<<endl; } } return 0; }