func_code_string: #include <bits/stdc++.h>   #pragma GCC optimize( Ofast )   #pragma GCC optimize( unroll-loops )   #pragma GCC target(         sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,tune=native )   using namespace std;   template <typename T1, typename T2>   void ckmin(T1 &a, T2 b) {     if (a > b) a = b;   }   template <typename T1, typename T2>   void ckmax(T1 &a, T2 b) {     if (a < b) a = b;   }   int read() {     int x = 0, f = 0;     char ch = getchar();     while (!isdigit(ch)) f |= ch ==  - , ch = getchar();     while (isdigit(ch)) x = 10 * x + ch -  0 , ch = getchar();     return f ? -x : x;   }   template <typename T>   void print(T x) {     if (x < 0) putchar( - ), x = -x;     if (x >= 10) print(x / 10);     putchar(x % 10 +  0 );   }   template <typename T>   void print(T x, char let) {     print(x), putchar(let);   }   const int mlen = 1 << 20;   const int N = mlen + 5;   const int mod = 998244353;   unsigned long long omgs[N];   int rev[N];   int qpow(int a, int b = mod - 2) {     int res = 1;     while (b) {       if (b & 1) res = 1ll * res * a % mod;       a = 1ll * a * a % mod;       b >>= 1;     }     return res;   }   const int G = qpow(3, (mod - 1) / mlen);   void setup() {     omgs[mlen / 2] = 1;     for (int i = mlen / 2 + 1; i < mlen; i++) omgs[i] = G * omgs[i - 1] % mod;     for (int i = mlen / 2 - 1; i > 0; i--) omgs[i] = omgs[i << 1];   }   int getR(int len) {     int lim = 1, L = 0;     while (lim <= len) lim <<= 1, L++;     for (int i = 0; i < lim; i++)       rev[i] = (rev[i >> 1] >> 1) | ((i & 1) << L - 1);     return lim;   }   inline void dft(vector<int> &a, int lim) {     a.resize(lim);     static unsigned long long A[N];     for (int i = 0; i < lim; i++) A[rev[i]] = a[i];     for (int mid = 1; mid < lim; mid <<= 1) {       for (int i = 0; i < lim; i += mid << 1) {         unsigned long long *W = omgs + mid;         for (int j = 0; j < mid; j++) {           unsigned long long tmp = *(W++) * A[i + j + mid] % mod;           A[i + j + mid] = A[i + j] + mod - tmp;           A[i + j] += tmp;         }       }     }     for (int i = 0; i < lim; i++) a[i] = A[i] % mod;   }   inline void idft(vector<int> &a, int lim) {     a.resize(lim);     dft(a, lim), reverse(a.begin() + 1, a.end());     int linv = mod - (mod - 1) / lim;     for (int i = 0; i < lim; i++) a[i] = 1ll * a[i] * linv % mod;   }   vector<int> operator*(vector<int> a, vector<int> b) {     int len = (int(a.size())) + (int(b.size())) - 1, lim = getR(len);     dft(a, lim), dft(b, lim);     for (int i = 0; i < lim; i++) a[i] = 1ll * a[i] * b[i] % mod;     idft(a, lim), a.resize(len);     return a;   }   vector<int> adj[N];   int n;   int son[N];   void dfs1(int u, int fa) {     for (auto v : adj[u]) {       if (v == fa) continue;       son[u]++;       dfs1(v, u);     }   }   int fac[N], ifac[N];   inline int C(int n, int m) {     return 1ll * fac[n] * ifac[n - m] % mod * ifac[m] % mod;   }   int main() {     setup();     n = read();     fac[0] = 1;     for (int i = 1; i <= n; i++) fac[i] = 1ll * fac[i - 1] * i % mod;     ifac[n] = qpow(fac[n]);     for (int i = n; i >= 1; i--) ifac[i - 1] = 1ll * ifac[i] * i % mod;     for (int i = 1; i <= n - 1; i++) {       int u = read(), v = read();       adj[u].push_back(v), adj[v].push_back(u);     }     dfs1(1, 0);     vector<int> f = {1};     sort(son + 1, son + n + 1, greater<int>());     for (int i = 1; i <= n; i++) {       int j = i;       while (j < n && son[i] == son[j + 1]) j++;       int up = j - i + 1;       vector<int> g(up + 1);       int cf = 1;       for (int i = 0; i <= up; i++) {         int coef = 1ll * C(up, i) * cf % mod;         g[i] = coef;         cf = 1ll * cf * (mod - son[j]) % mod;       }       f = f * g;       i = j;     }     int ans = 0;     for (int i = 0; i <= n - 1; i++) ans = (ans + 1ll * fac[n - i] * f[i]) % mod;     print(ans,   n );     return 0;   }   