#include <bits/stdc++.h>
using namespace std;
using pi = pair<int, int>;
const int BLOCK = 300;
void build_dist_arr(int N,
const vector<vector<int>> &radj,
vector<vector<pi>> &anc)
{
for (int i = 0; i < N; i++)
{
vector<int> dists(N, -1);
vector<int> from;
for (auto &parent : radj[i])
{
for (auto &[d, f] : anc[parent])
{
if (f == -1)
break;
if (dists[f] == -1)
{
dists[f] = d + 1;
from.push_back(f);
}
else
{
if (dists[f] < d + 1)
{
dists[f] = d + 1;
}
}
}
}
from.push_back(i);
dists[i] = 0;
sort(from.begin(), from.end(), [&](int a, int b)
{ return dists[a] > dists[b]; });
for (int j = 0; j < BLOCK && j < from.size(); j++)
{
anc[i][j] = {dists[from[j]], from[j]};
}
}
}
int search(int node, const vector<vector<int>> &adj, const unordered_set<int> &busy)
{
vector<int> mx(node + 1, 0);
for (int i = 0; i < node; i++)
{
for (auto &child : adj[i])
{
if (child > node)
continue;
if (busy.count(i) == 0 || mx[i] > 0)
mx[child] = max(mx[child], mx[i] + 1);
}
}
if (mx[node] == 0)
{
if (busy.count(node))
return -1;
}
return mx[node];
}
int scan(int node, const vector<vector<pi>> &anc, const unordered_set<int> &busy)
{
for (auto &[dist, from] : anc[node])
{
if (busy.count(from))
continue;
return dist;
}
return -1;
}
int main()
{
#if defined(DEBUG)
freopen("test.in", "r", stdin);
freopen("test.out", "w", stdout);
#else
cin.tie(0)->sync_with_stdio(false);
#endif
int N, M, Q;
cin >> N >> M >> Q;
vector<vector<int>> adj(N);
vector<vector<int>> radj(N);
for (int i = 0; i < M; i++)
{
int a, b;
cin >> a >> b;
a--, b--;
adj[a].push_back(b);
radj[b].push_back(a);
}
vector<vector<pi>> ancestors(N, vector<pi>(BLOCK, {-1, -1}));
build_dist_arr(N, radj, ancestors);
for (int q = 0; q < Q; q++)
{
int T, Y;
cin >> T >> Y;
T--;
unordered_set<int> busy;
for (int _ = 0; _ < Y; _++)
{
int y;
cin >> y;
y--;
busy.insert(y);
}
if (Y >= BLOCK)
{
cout << search(T, adj, busy) << "\n";
}
else
{
cout << scan(T, ancestors, busy) << "\n";
}
}
cout << flush;
}
