#include "bits/stdc++.h" using namespace std; #ifdef debug #include "debug.hpp" #else #define dbg(...) #define dbgx(x) #define line() #endif #define int long long #define vi vector<int> #define vvi vector<vi> #define pii pair<int, int> #define size(x) (int)(x.size()) const int N = 25; int n, m, p; vi adj[N]; vi force(N); int ans = 0; void dfs(int u, set<int> st) { for (int &v : adj[u]) { set<int> nw = st; nw.insert(v); dfs(v, nw); } bool ok = true; for (int i = 1; i <= p; ++i) { if (st.find(force[i]) == st.end()) ok = false; } if (ok == true) ++ans; } void _() { cin >> n >> m >> p; for (int i = 1; i <= p; ++i) cin >> force[i]; while (m--) { int u, v; cin >> u >> v; adj[u].push_back(v); } dfs(1, {1}); cout << ans << '\n'; } signed main() { ios::sync_with_stdio(false); cin.tie(nullptr); // freopen("in.txt", "r", stdin); int t = 1; // cin >> t; for (int cs = 1; cs <= t; ++cs) { _(); } return 0; }