#include<bits/stdc++.h>
#define cir(i,a,b) for(int i=a;i<b;++i)
using namespace std;
using lint=long long;
static constexpr auto MOD=998244353;
class mathbase{
private:
    vector<lint> fct;
public:
    constexpr auto qpow(lint a,auto b) const{
        auto res=1ll;
        while(b){
            if(b&1) (res*=a)%=MOD;
            (a*=a)%=MOD;b>>=1;
        }
        return res;
    }
    constexpr auto inv(auto x) const{return qpow(x,MOD-2);}
    auto init(const auto n){
        fct.resize(n,1);
        cir(i,1,n) fct[i]=fct[i-1]*i%MOD;
    }
    auto fact(const auto x) const{return fct[x];}
    // static constexpr const auto lowbit(signed int x) noexcept(true)->
} math;
class tree{
private:
    vector<vector<int>> gr;
    vector<vector<lint>> uf,ug,uh;
    auto dfs(int u,int f=-1)->int{
        const auto n=(int)(gr.size());
        auto siz=0;
        uh[u][0]=1;
        for(auto&i:gr[u]) if(i!=f){
            const auto szv=dfs(i,u);
            vector<lint> cf(n+1),cg(n+1),ch(n+1);
            cir(w,0,siz+1) cir(vw,0,szv+1){
                (cf[w+vw]+=uf[u][w]*ug[i][vw]+uh[u][w]*uf[i][vw])%=MOD;
                (cg[w+vw]+=ug[u][w]*ug[i][vw])%=MOD;
                (ch[w+vw]+=uh[u][w]*ug[i][vw])%=MOD;
                (cg[w+vw+1]+=uf[u][w]*uf[i][vw]*2)%=MOD;
            }
            uf[u]=cf;ug[u]=cg;uh[u]=ch;
            siz+=szv;
        }
        ++siz;
        cir(i,0,siz) (ug[u][i+1]+=uf[u][i]*2+uh[u][i])%=MOD;
        cir(i,0,siz+1) (uf[u][i]+=uh[u][i])%=MOD;
        return siz;
    }
public:
    auto link(int u,int v){
        gr[u].emplace_back(v);
        gr[v].emplace_back(u);
    }
    auto init(){
        dfs(0);
        return ug[0];
    }
    tree(int _n):
        gr(_n),
        uf(_n,vector<lint>(_n+1)),
        ug(_n,vector<lint>(_n+1)),
        uh(_n,vector<lint>(_n+1)){}
};
auto init_q(const int n){
    vector q(n,vector<lint>(n));
    q[0][0]=1;
    cir(i,1,n) cir(j,1,n){
        (q[i][j]=q[i-1][j]*(i+j-1)+q[i-1][j-1])%=MOD;
    }
    cir(i,0,5){
        cir(j,0,5){
            clog<<q[i][j]<<' ';
        }
        clog<<'\n';
    }
    return q;
}
static constexpr auto maxn=(int)(5e3+7);
int main(){
    ios::sync_with_stdio(false),cin.tie(nullptr);
    int n;cin>>n;vector<lint> f{1};
    math.init(maxn);
    auto siz=0;
    const auto q=init_q(maxn);
    cir(c,0,n){
        int m;cin>>m;tree gr(m);
        cir(i,0,m-1){
            int u,v;cin>>u>>v;--u;--v;
            gr.link(u,v);
        }
        auto g=gr.init();
        cir(i,0,m+1) cir(j,0,i) (g[j]+=((i-j)&1?(MOD-1):1)*q[i][j]%MOD*g[i])%=MOD;
        const auto lf=f;
        f=vector<lint>((siz+=m)+1);
        cir(i,0,(int)(lf.size())) cir(j,0,m+1) (f[i+j]+=lf[i]*g[j])%=MOD; 
    }
    auto ans=0ll;
    cir(i,1,(int)(f.size())) (ans+=f[i]*math.fact(i-1))%=MOD;
    cout<<ans<<'\n';
    return 0;
}