// #include <bits/stdc++.h> #include <iostream> #include <cmath> #include <algorithm> #include <map> #include <vector> #include <iomanip> #include <string> #include <queue> #include <set> #include <deque> #include <numeric> #include <cassert> #include <chrono> using namespace std; void fast_io(){ // freopen("", "r", stdin); // freopen("", "w", stdout); ios::sync_with_stdio(0); cin.tie(); cout.tie(); cout << setprecision(9); } #define endl '\n' #define a(v) (v).begin(), (v).end() #define ra(v) (v).rbegin(), (v).rend() #define fi first #define se second const int N = 1e5 + 5; int n, m, q, indeg[N], ans[N]; vector<int> topo, adj[N]; vector<pair<int, int>> L[N]; vector<pair<int, int>> merge(vector<pair<int, int>> x, vector<pair<int, int>> y){ vector<pair<int, int>> z; int i = 0, j = 0; while (i < (int) x.size() && j < (int) y.size()){ if (x[i].fi + 1 > y[j].fi) {z.push_back({x[i].fi + 1, x[i].se}); i++;} else {z.push_back(y[j]); j++;} } while (i < (int) x.size()) {z.push_back({x[i].fi + 1, x[i].se}); i++;}; while (j < (int) y.size()) {z.push_back(y[j]); j++;}; int M = z.size(); vector<pair<int, int>> ans; for (int ii = 0; ii < M; ii++){ if (ii + 1 < M && z[ii].second == z[ii + 1].second) continue; ans.push_back(z[ii]); } while (ans.size() > 300) ans.pop_back(); return ans; } void init(){ queue<int> q; for (int i = 1; i <= n; i++) L[i].push_back({0, i}); for (int i = 1; i <= n; i++) if (indeg[i] == 0) q.push(i); while (q.size()){ int u = q.front(); q.pop(); topo.push_back(u); for (auto v : adj[u]){ indeg[v]--; if (indeg[v] == 0) q.push(v); } } for (auto u : topo){ for (auto v : adj[u]){ L[v] = merge(L[u], L[v]); } } } void solve() { cin >> n >> m >> q; for (int i = 1; i <= m; i++){ int u, v; cin >> u >> v; indeg[v]++; adj[u].push_back(v); } init(); for (int Q = 1; Q <= q; Q++){ int T, Y; cin >> T >> Y; int C[Y + 1]; map<int, bool> c; for (int i = 1; i <= Y; i++) { cin >> C[i]; c[C[i]] = 1; } if (Y <= 300) { if (q == 1 && n > 300) assert(0); bool bb = 0; int S = min(300, (int) L[T].size()); for (int i = 0; i < S; i++){ if (!c[L[T][i].second]){ cout << L[T][i].first << endl; bb = 1; break; } } if (!bb) cout << -1 << endl; } else { for (int i = 1; i <= Y; i++){ ans[C[i]] = -1e9; } for (auto u : topo){ for (auto v : adj[u]){ ans[v] = max(ans[v], ans[u] + 1); } } if (ans[T] < 0) cout << -1 << endl; else cout << ans[T] << endl; } } return; } signed main() { fast_io(); srand(chrono::steady_clock::now().time_since_epoch().count()); int tc = 1; // cin >> tc; while (tc--) solve(); return 0; }