// Copyright © 2022 Youngmin Park. All rights reserved.
//#pragma GCC optimize("O3")
//#pragma GCC target("avx2")
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using vi = vector<int>;
using pii = pair<int, int>;
using vpi = vector<pii>;
using pll = pair<ll, ll>;
using vl = vector<ll>;
using vpl = vector<pll>;
using ld = long double;
template <typename T, size_t SZ>
using ar = array<T, SZ>;
template <typename T>
using pqg = priority_queue<T, vector<T>, greater<T>>;
#define all(v) (v).begin(), (v).end()
#define pb push_back
#define sz(x) (int)(x).size()
#define fi first
#define se second
#define lb lower_bound
#define ub upper_bound
constexpr int INF = 1e9;
constexpr ll LINF = 1e18;
const ld PI = acos((ld)-1.0);
constexpr int dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1};
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
template <typename T>
constexpr bool ckmin(T &a, const T &b) { return b < a ? a = b, 1 : 0; }
template <typename T>
constexpr bool ckmax(T &a, const T &b) { return b > a ? a = b, 1 : 0; }
template <typename A, typename B>
ostream &operator<<(ostream &os, const pair<A, B> &p)
{
return os << '(' << p.first << ", " << p.second << ')';
}
template <typename T_container, typename T = typename enable_if<!is_same<T_container, string>::value, typename T_container::value_type>::type>
ostream &operator<<(ostream &os, const T_container &v)
{
os << '{';
string sep;
for (const T &x : v)
os << sep << x, sep = ", ";
return os << '}';
}
template <typename T>
ostream &operator<<(ostream &os, const deque<T> &v) {
os << vector<T>(all(v));
return os;
}
template <typename T, typename S, typename C>
ostream &operator<<(ostream &os, priority_queue<T, S, C> pq) {
vector<T> v;
while (sz(pq)) {
v.pb(pq.top());
pq.pop();
}
os << v;
return os;
}
void dbg_out()
{
cerr << "\033[0m" << endl;
}
template <typename Head, typename... Tail>
void dbg_out(Head H, Tail... T)
{
cerr << ' ' << H;
dbg_out(T...);
}
#ifdef LOCAL
#define dbg(...) cerr << "\033[1;35m(" << #__VA_ARGS__ << "):\033[33m", dbg_out(__VA_ARGS__)
#else
#define dbg(...) 42
#endif
inline namespace RecursiveLambda
{
template <typename Fun>
struct y_combinator_result
{
Fun fun_;
template <typename T>
explicit y_combinator_result(T &&fun) : fun_(forward<T>(fun)) {}
template <typename... Args>
decltype(auto) operator()(Args &&...args)
{
return fun_(ref(*this), forward<Args>(args)...);
}
};
template <typename Fun>
decltype(auto) y_combinator(Fun &&fun)
{
return y_combinator_result<decay_t<Fun>>(forward<Fun>(fun));
}
};
inline namespace Range {
class ForwardRange {
int src, dst;
public:
explicit constexpr ForwardRange(const int l, const int r) : src(l), dst(r) {}
explicit constexpr ForwardRange(const int n) : src(0), dst(n) {}
constexpr ForwardRange begin() const { return *this; }
constexpr monostate end() const { return {}; }
constexpr bool operator!=(monostate) const { return src < dst; }
constexpr void operator++() const {}
constexpr int operator*() { return src++; }
};
class BackwardRange {
int src, dst;
public:
explicit constexpr BackwardRange(const int l, const int r) : src(r), dst(l) {}
explicit constexpr BackwardRange(const int n) : src(n), dst(0) {}
constexpr BackwardRange begin() const { return *this; }
constexpr monostate end() const { return {}; }
constexpr bool operator!=(monostate) const { return src > dst; }
constexpr void operator++() const {}
constexpr int operator*() { return --src; }
};
using rep = ForwardRange;
using per = BackwardRange;
};
void solve()
{
int n, m, q;
cin >> n >> m >> q;
const int SQ = sqrt(n);
vector<vi> adj(n), radj(n), queries(q);
vector<vpi> dp(n);
vi t(q);
for (int i : rep(m)) {
int u, v;
cin >> u >> v, u--, v--;
adj[u].pb(v), radj[v].pb(u);
}
for (int i : rep(n)) {
map<int, int> dist;
dist[i] = 0;
for (int j : radj[i]) {
for (auto &[v, d] : dp[j]) ckmax(dist[v], d + 1);
}
vpi tmp(all(dist));
sort(all(tmp), [&](auto x, auto y) {
return x.se > y.se;
});
if (sz(tmp) <= SQ) swap(tmp, dp[i]);
else{
dp[i].insert(dp[i].begin(), tmp.begin(), tmp.begin() + SQ);
}
vpi().swap(tmp);
}
dbg(dp);
vector<bool> busy(n);
vi DP(n);
auto naiveDP = [&](int t, vi& C) -> int {
for (int i : rep(n)) DP[i] = 0;
for (int i : C) DP[i] = -1;
for (int i : rep(t + 1)) {
for (int j : radj[i]) {
if (DP[j] >= 0) ckmax(DP[i], DP[j] + 1);
}
}
return DP[t];
};
for (int i : rep(q)) {
cin >> t[i];
t[i]--;
int x;
cin >> x;
queries[i].resize(x);
for (auto &e : queries[i]) cin >> e, e--, busy[e] = 1;
if (x >= SQ) {
cout << naiveDP(t[i], queries[i]) << '\n';
}else{
int ans = -1;
for (auto &[v, d] : dp[t[i]]) {
if (!busy[v]) ckmax(ans, d);
}
cout << ans << '\n';
}
for (auto &e : queries[i]) busy[e] = 0;
}
}
int main()
{
cin.tie(0)->sync_with_stdio(0);
cin.exceptions(cin.failbit);
int testcase = 1;
// cin >> testcase;
while (testcase--)
{
solve();
}
#ifdef LOCAL
cerr << "Time elapsed: " << 1.0 * (double)clock() / CLOCKS_PER_SEC << " s.\n";
#endif
}
