#include <bits/stdc++.h> using namespace std; #define all(x) x.begin(), x.end() const int inf = -1; const int binf = -1e6; const int mxN = 2e5 + 100; const int mxB = 343; vector<pair<int, int>> path[mxN]; vector<int> adj[mxN], radj[mxN]; signed main(){ ios::sync_with_stdio(0); cin.tie(nullptr); cout.tie(nullptr); int n, m, q; cin >> n >> m >> q; vector<int> mn(n + 1, inf), vis(n + 1, 0), dp(n + 1, binf); for(int i = 0, u, v; i < m; ++i){ cin >> u >> v; --u, --v; adj[u].push_back(v); radj[v].push_back(u); } auto dfs = [&](auto &self, int u) -> int { if(vis[u]) return binf; if(dp[u] != binf) return 0; int ans = 0; for(auto it : radj[u]){ ans = max(ans, self(self, it) + 1); } return dp[u] = ans; }; for(int i = 0; i < n; ++i){ path[i].push_back({i, 0}); vector<int> all_node; for(auto it : radj[i]){ for(auto [v, w] : path[it]){ if(mn[v] == inf){ all_node.push_back(v); mn[v] = w + 1; }else if(mn[v] < w + 1){ mn[v] = w + 1; } } } for(auto it : all_node){ path[i].push_back({it, mn[it]}); } sort(all(path[i]), [&](pair<int, int> p1, pair<int, int> p2){ return p1.second > p2.second; }); while(path[i].size() > mxB) path[i].pop_back(); for(auto it : all_node) mn[it] = -1; } while(q--){ int x, y; cin >> x >> y; --x; vector<int> ban; while(y--){ int u; cin >> u; --u; vis[u] = 1; ban.push_back(u); } if(1){ for(int j = 1; j <= n; ++j) dp[j] = binf; int ans = dfs(dfs, x); cout << max(ans, -1) << "\n"; }else{ int ans = inf; for(auto [u, w] : path[x]){ if(vis[u] == 0){ ans = max(ans, w); } } cout << ans << "\n"; } for(auto it : ban) vis[it] = 0; } return 0; }