func_code_string: #include <bits/stdc++.h>   using namespace std;   const long long MAX_N = 3e5 + 7;   const long long MOD = 998244353;   long long n;   long long deg[MAX_N], fac[MAX_N];   long long f_pow(long long base, long long b, long long mod) {     long long res = 1;     while (b) {       if (b & 1) res = res * base % mod;       base = base * base % mod;       b >>= 1;     }     return res;   }   namespace NTT {   const long long MAX_N = 3e6 + 7;   const long long MOD = 998244353;   const long long G = 3;   long long rev[MAX_N];   long long f[MAX_N], g[MAX_N];   long long n, m;   vector<vector<long long>> p;   struct Poly {     long long n;     vector<long long> p;     Poly(vector<long long> _p = {}, long long _n = 0) : n(_n) {       n = _p.size();       p.resize(n);       for (long long i = 0; i < n; ++i) p[i] = _p[i];     }     bool operator<(const Poly &a) const { return n > a.n; }   };   void ntt(long long *a, long long n, long long dft) {     for (long long i = 0; i < n; i++) {       if (i < rev[i]) swap(a[i], a[rev[i]]);     }     for (long long i = 1; i < n; i <<= 1) {       long long wn = f_pow(G, (MOD - 1) / (i << 1), MOD);       if (dft < 0) wn = f_pow(wn, MOD - 2, MOD);       for (long long j = 0; j < n; j += (i << 1)) {         long long wnk = 1;         for (long long k = j; k < j + i; k++) {           long long a1 = a[k], a2 = a[k + i];           a[k] = (a1 + wnk * a2 % MOD) % MOD;           a[k + i] = (a1 - wnk * a2 % MOD) % MOD;           wnk = wnk * wn % MOD;         }       }     }     if (dft == -1) {       long long inv = f_pow(n, MOD - 2, MOD);       for (long long i = 0; i < n; i++) a[i] = a[i] * inv % MOD;     }   }   vector<long long> merge(const vector<long long> &F,                           const vector<long long> &G) {     n = F.size() - 1, m = G.size() - 1;     long long N = 1, p = 0;     while (N < (m + n + 1)) N <<= 1, ++p;     for (long long i = 0; i < N; ++i) rev[i] = f[i] = g[i] = 0;     for (long long i = 0; i < N; ++i)       rev[i] = ((rev[i >> 1] >> 1) | ((i & 1) << (p - 1)));     for (long long i = 0; i <= n; ++i) f[i] = F[i];     for (long long i = 0; i <= m; ++i) g[i] = G[i];     ntt(f, N, 1), ntt(g, N, 1);     for (long long i = 0; i < N; ++i) f[i] = f[i] * g[i] % MOD;     ntt(f, N, -1);     vector<long long> res(m + n + 1);     for (long long i = 0; i <= n + m; ++i) res[i] = (f[i] + MOD) % MOD;     return res;   }   vector<long long> div_ntt(long long l, long long r) {     if (l == r) return p[l];     long long mid = (l + r) >> 1;     vector<long long> F = div_ntt(l, mid), G = div_ntt(mid + 1, r);     return merge(F, G);   }   void merge(long long idx_f, long long idx_g) {     vector<long long> &F = p[idx_f];     vector<long long> &G = p[idx_g];     n = F.size() - 1, m = G.size() - 1;     long long N = 1, p = 0;     while (N < (m + n + 1)) N <<= 1, p++;     for (long long i = 0; i < N; ++i) rev[i] = f[i] = g[i] = 0;     for (long long i = 0; i < N; i++)       rev[i] = ((rev[i >> 1] >> 1) | ((i & 1) << (p - 1)));     for (long long i = 0; i <= n; i++) f[i] = F[i];     for (long long i = 0; i <= m; i++) g[i] = G[i];     ntt(f, N, 1);     ntt(g, N, 1);     for (long long i = 0; i < N; i++) {       f[i] = f[i] * g[i] % MOD;     }     ntt(f, N, -1);     F.resize(m + n + 1);     for (long long i = 0; i <= (n + m); ++i) F[i] = (f[i] + MOD) % MOD;   }   vector<long long> solve() {     priority_queue<Poly> q;     for (long long i = 0; i < p.size(); ++i) q.push(Poly(p[i]));     while (q.size() > 1) {       vector<long long> F = q.top().p;       q.pop();       vector<long long> G = q.top().p;       q.pop();       q.push(Poly(merge(F, G)));     }     return q.top().p;   }   vector<long long> solve(long long l, long long r) { return div_ntt(l, r); }   }  // namespace NTT   signed main() {     scanf( %lld , &n);     for (long long i = 1; i < n; ++i) {       long long x, y;       scanf( %lld%lld , &x, &y);       ++deg[x], ++deg[y];     }     for (long long i = 2; i <= n; ++i) --deg[i];     for (long long i = 1; i <= n; ++i) {       vector<long long> t;       t.push_back(1ll);       if (deg[i]) t.push_back(deg[i]);       NTT::p.push_back(t);     }     vector<long long> F = NTT::solve();     long long ans = 0, flag = 1;     fac[0] = 1;     for (long long i = 1; i <= n; ++i) fac[i] = fac[i - 1] * i % MOD;     for (long long i = 0; i < n && i < F.size(); ++i) {       ans = (ans + flag * F[i] * fac[n - i] % MOD) % MOD;       flag = -flag;     }     printf( %lld n , (ans + MOD) % MOD);     return 0;   }   