#include "bits/stdc++.h" #include #include #include "atcoder/all" #include //#include //using namespace boost::multiprecision; // std::fixed << std::setprecision(10) << using namespace std; using namespace atcoder; using ll = long long; using ull = unsigned long long; using mint = modint998244353; using mint2 = modint1000000007; const double eps = 1e-9; #define REP(i, n) for (ll i = 0; i < ll(n); ++i) #define REPI(i, init, n) for (ll i = init; i < ll(n); ++i) #define REPD(i, init) for (ll i = init; i >=0; --i) #define REPDI(i, init, n) for (ll i = init; i >=n; --i) #define REPE(i, c) for (const auto& i : c) #define TCASE() ll _ttt; cin >> _ttt; while(_ttt--) using vl = vector; using vvl = vector>; #define VL(a, n) vector a; a.assign(n, 0); #define VLI(a, n) vector a; a.assign(n, 0); for(auto& x : a) cin >> x; #define VSI(a, n) vector a; a.assign(n, ""); for(auto& x : a) cin >> x; #define VVLI(a, n, m, init) vector> a(n); for(auto& x : a) x.assign(m, init); using vd = vector; using pl = pair; struct uv { ll u; ll v; ll c; }; #define VUVI(a, n) vector a; a.assign(n, {0, 0, 1}); for(auto& x : a) {cin >> x.u >> x.v; x.u--; x.v--;} #define VUVCI(a, n) vector a; a.assign(n, {0, 0, 0}); for(auto& x : a) {cin >> x.u >> x.v >> x.c; x.u--; x.v--;} vvl to_edge(const ll n, const vector& v) { vvl ret(n); for (auto& x : v) ret[x.u].push_back(x.v); return ret; } vvl to_edge_d(const ll n, const vector& v) { vvl ret(n); for (auto& x : v) { ret[x.u].push_back(x.v); ret[x.v].push_back(x.u); } return ret; } template using pql = priority_queue; template using pqg = priority_queue, greater>; using vm = vector; using vvm = vector; void yn(bool f) { std::cout << (f ? "Yes" : "No") << endl; }; template void ov(const T& v) { for (auto it = v.begin(); it != v.end(); it++) { if (it != v.begin()) cout << " "; cout << *it; } }; template<> void ov(const vm& v) { for (auto it = v.begin(); it != v.end(); it++) { if (it != v.begin()) cout << " "; cout << it->val(); } }; const ll llhuge = 1LL << 60; //十分でかいが多少足しても溢れない数値 auto gmax(const auto& a, const auto& b) { return a > b ? a : b; }; auto gmin(const auto& a, const auto& b) { return a < b ? a : b; }; template bool chmin(T& a, const U& b) { const T olda = a; a = gmin(a, b); return olda != a; } template bool chmax(T& a, const U& b) { const T olda = a; a = gmax(a, b); return olda != a; } template void mysort(T& v) { std::sort(begin(v), end(v)); }; template void mysort(T& v, U pr) { std::sort(begin(v), end(v), pr); }; template void myrev(T& v) { std::reverse(begin(v), end(v)); }; template [[nodiscard]] V myat(const T& mp, const K& key) { return mp.find(key) == mp.end() ? V() : mp.at(key); } struct xy { ll x; ll y; }; //階乗 mint fact(const ll n) { mint ret = 1; REPI(i, 1, n + 1) ret *= i; return ret; } int main() { cin.tie(nullptr); ios::sync_with_stdio(false); ll n, m, k; cin >> n >> m >> k; vector v(k); REP(i, k) { cin >> v[i].x >> v[i].y; v[i].x--; v[i].y--; } if (k > 0) { map mp; REP(i, k) { mp[v[i].x] = 0; mp[v[i].y] = 0; } ll mc = mp.size(); { ll i = 0; REPE(e, mp) { mp[e.first] = i; if (e.first >= m) chmin(mc, i); i++; } } REP(i, k) { v[i].x = mp[v[i].x]; v[i].y = mp[v[i].y]; } vl needs(mp.size(), 0); REP(i, k) { needs[v[i].y] |= 1LL << v[i].x; } ll nn = n; //残りのヒロイン ll mn = m; //残りのサブヒロイン REPE(e, mp) { if (e.first < m) mn -= 1; nn -= 1; } vector dp(2, vm(1 << mp.size(), 0)); dp[0][0] = 1; //ヒロインから dp[1][0] = 1; //サブから REP(i, 1LL << mp.size()) { REP(x, 2) { REP(j, mp.size()) { if (!(i & (1LL << j))) continue; ll old = i ^ (1LL << j); if (old == 0 && j < mc && x == 0) continue; if (old == 0 && j >= mc && x == 1) continue; if ((old & needs[j]) != needs[j]) continue; //不足 dp[x][i] += dp[x][old]; } } } ll sz = mp.size(); mint ans = 0; //dpのヒロインが最初に来るパターンの組み合わせ ans += dp[0][(1 << sz) - 1] * fact(nn + sz - 1) / fact(sz - 1); //dp外のヒロインが最初に来るパターンの組み合わせ ans += (nn - mn) * (dp[0][(1 << sz) - 1] + dp[1][(1 << sz) - 1]) * fact(nn - 1 + sz) / fact(sz); cout << ans.val() << endl; } else { mint ans = (n - m) * fact(n - 1); cout << ans.val() << endl; } }