#include <iostream>
#include <vector>

typedef long long ll;
typedef double lf;

// #define DEBUG 1
struct IO
{
    #define MAXSIZE (1 << 20)
    #define isdigit(x) (x >= '0' && x <= '9')
    char buf[MAXSIZE], *p1, *p2;
    char pbuf[MAXSIZE], *pp;
    #if DEBUG
    #else
    IO() : p1(buf), p2(buf), pp(pbuf) {}
    ~IO() {fwrite(pbuf, 1, pp - pbuf, stdout);}
    #endif
    #define gc() (p1 == p2 && (p2 = (p1 = buf) + fread(buf, 1, MAXSIZE, stdin), p1 == p2) ? ' ' : *p1++)
    #define blank(x) (x == ' ' || x == '\n' || x == '\r' || x == '\t')

    template <typename T>
    void Read(T &x)
    {
        #if DEBUG
        std::cin >> x;
        #else
        bool sign = 0; char ch = gc(); x = 0;
        for (; !isdigit(ch); ch = gc())
            if (ch == '-') sign = 1;
        for (; isdigit(ch); ch = gc()) x = x * 10 + (ch ^ 48);
        if (sign) x = -x;
        #endif
    }
    void Read(char *s)
    {
        #if DEBUG
        std::cin >> s;
        #else
        char ch = gc();
        for (; blank(ch); ch = gc());
        for (; !blank(ch); ch = gc()) *s++ = ch;
        *s = 0;
        #endif
    }
    void Read(char &c) {for (c = gc(); blank(c); c = gc());}

    void Push(const char &c)
    {
        #if DEBUG
        putchar(c);
        #else
        if (pp - pbuf == MAXSIZE) fwrite(pbuf, 1, MAXSIZE, stdout), pp = pbuf;
        *pp++ = c;
        #endif
    }
    template <typename T>
    void Write(T x)
    {
        if (x < 0) x = -x, Push('-');
        static T sta[35];
        int top = 0;
        do sta[top++] = x % 10, x /= 10; while (x);
        while (top) Push(sta[--top] ^ 48);
    }
    template <typename T>
    void Write(T x, char lst) {Write(x), Push(lst);}
} IO;
#define Read(x) IO.Read(x)
#define Write(x, y) IO.Write(x, y)
#define Put(x) IO.Push(x)

using namespace std;

const int MAXN = 5010, MAXM = 310, mod = 998244353;

int n, m, N[MAXM];
ll S[MAXN][MAXN], fac[MAXN];
ll dp[MAXM][MAXN], h[MAXN];

vector <int> e[MAXN];
ll f[MAXN][MAXN][4], g[MAXN][4];
int sz[MAXN];

void DFS(int u, int fa)
{
    sz[u] = 1;
    f[u][1][0] = f[u][1][1] = f[u][1][2] = 0;
    f[u][1][3] = 1;
    for (auto v : e[u])
    {
        if (v == fa) continue;
        DFS(v, u);
        for (int i = 1; i <= sz[u] + sz[v]; i++) g[i][0] = g[i][1] = g[i][2]  = g[i][3] = 0;
        for (int i = sz[u]; i; i--)
            for (int j = sz[v]; j; j--)
            {
                for (int x = 0; x < 4; x++)
                    for (int y = 0; y < 4; y++)
                    {
                        g[i + j][x] = (g[i + j][x] + f[u][i][x] * f[v][j][y]) % mod;
                        if ((x == 1 || x == 3) && (y == 2 || y == 3))
                            g[i + j - 1][x == 3 ? 2 : 0] = (g[i + j - 1][x == 3 ? 2 : 0] + f[u][i][x] * f[v][j][y]) % mod;
                        if ((x == 2 || x == 3) && (y == 1 || y == 3))
                            g[i + j - 1][x == 3 ? 1 : 0] = (g[i + j - 1][x == 3 ? 1 : 0] + f[u][i][x] * f[v][j][y]) % mod;
                    }
            }
        sz[u] += sz[v];
        for (int i = 1; i <= sz[u] + sz[v]; i++)
            for (int j = 0; j < 4; j++)
                f[u][i][j] = g[i][j];
    }
}


int main()
{
    // freopen("B.in", "r", stdin);
    // freopen("B.out", "w", stdout);
    #if DEBUG
    #else
    ios::sync_with_stdio(0), cin.tie(0);
    #endif

    S[1][1] = 1;
    for (int i = 2; i < MAXN; i++)
        for (int j = 1; j <= i; j++)
            S[i][j] = (S[i - 1][j - 1] + S[i - 1][j] * (i + j - 1) % mod) % mod;
    fac[0] = 1;
    for (int i = 1; i < MAXN; i++) fac[i] = fac[i - 1] * i % mod;

    Read(m);
    for (int t = 1; t <= m; t++)
    {
        Read(n); N[t] = n;
        for (int i = 1; i <= n; i++) e[i].clear();
        for (int i = 1, u, v; i < n; i++) Read(u), Read(v), e[u].push_back(v), e[v].push_back(u);
        DFS(1, 0);
        for (int i = 1; i <= n; i++) f[1][i][0] = (f[1][i][0] + f[1][i][1] + f[1][i][2] + f[1][i][3]) % mod;
        for (int i = 1; i <= n; i++)
            for (int j = n - i; j < n; j++)    
                dp[t][j] = (dp[t][j] + f[1][i][0] * S[i][n - j] % mod * ((n - i) & 1 ? -1 : 1)) % mod;
    }
    for (int t = 2; t <= m; t++)
    {
        for (int i = 0; i < N[t - 1] + N[t]; i++) h[i] = 0;
        for (int i = N[t - 1] - 1; ~i; i--)
            for (int j = N[t] - 1; ~j; j--)
                h[i + j] = (h[i + j] + dp[t - 1][i] * dp[t][j]) % mod;
        N[t] += N[t - 1];
        for (int i = 0; i < N[t]; i++) dp[t][i] = h[i];
    }
    ll ans = 0;
    for (int i = 0; i < N[m]; i++)
        ans = (ans + dp[m][i] * fac[N[m] - i - 1] % mod * (i & 1 ? -1 : 1)) % mod;
    cout << (ans + mod) % mod << '\n';
    return 0;
}