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 #include<bits/stdc++.h> using namespace std;
#define get64(a,b) ((a)*2000000000ll+(b)) typedef pair<int,int> pii; #define __int64 long long
const int maxn=2e5+5;
int head[maxn]; int to[maxn*2],nex[maxn*2],tot; inline void _addedge(int u,int v){to[++tot]=v,nex[tot]=head[u],head[u]=tot;} inline void addedge(int u,int v){_addedge(u,v),_addedge(v,u);} void deltree(int rt,int father){ for(int i=head[rt];i;i=nex[i]) if(to[i]!=father) deltree(to[i],rt); head[rt]=0; }
int pw[maxn*2]={1},hshmod; int *hsh,siz[maxn]; int *ehsh; void dfs(int u,int father){ siz[u]=1; for(int i=head[u];i;i=nex[i]){ if(to[i]==father)continue; dfs(to[i],u), siz[u]+=siz[to[i]]; } } void dfs1(int u,int father){ for(int i=head[u];i;i=nex[i]){ if(to[i]==father) continue; dfs1(to[i],u);
vector<pii>buf; for(int j=head[to[i]];j;j=nex[j]){ if(to[j]==u) continue; buf.emplace_back(ehsh[j],2*siz[to[j]]); } sort(buf.begin(),buf.end()); ehsh[i]=1; for(pii x:buf) ehsh[i]=(1ll*ehsh[i]*pw[x.second]+x.first)%hshmod; ehsh[i]=(1ll*ehsh[i]*pw[1]+2)%hshmod; } } void dfs2(int u,int father,int rt){ vector<pii>buf; for(int i=head[u];i;i=nex[i]) { if(to[i]==father) buf.emplace_back(ehsh[i],2*(siz[rt]siz[u])); else buf.emplace_back(ehsh[i],2*siz[to[i]]); } sort(buf.begin(),buf.end()); hsh[u]=1; for(pii x:buf) hsh[u]=(1ll*hsh[u]*pw[x.second]+x.first)%hshmod; hsh[u]=(1ll*hsh[u]*pw[1]+2)%hshmod;
vector<pii>pre(buf),suf(buf); int sz=suf.size(); for(int i=1,j=sz2;i<sz;i++,j){ pre[i].first=(1ll*pre[i1].first*pw[pre[i].second]+pre[i].first)%hshmod; suf[j].first=(1ll*suf[j].first*pw[suf[j+1].second]+suf[j+1].first)%hshmod; pre[i].second+=pre[i1].second; suf[j].second+=suf[j+1].second; }
for(int i=head[u];i;i=nex[i]){ if(father==to[i]) continue; ehsh[i^1]=1; int idx=lower_bound(buf.begin(),buf.end(),pii(ehsh[i],2*siz[to[i]]))buf.begin(); if(idx1>=0) ehsh[i^1]=(1ll*ehsh[i^1]*pw[pre[idx1].second]+pre[idx1].first)%hshmod; if(idx+1<sz) ehsh[i^1]=(1ll*ehsh[i^1]*pw[suf[idx+1].second]+suf[idx+1].first)%hshmod; ehsh[i^1]=(1ll*ehsh[i^1]*pw[1]+2)%hshmod; dfs2(to[i],u,rt); } } void treehash(int u,int*hsh_,int*ehsh_,int base,int hshmod_){ hsh=hsh_,ehsh=ehsh_,hshmod=hshmod_; dfs(u,0); for(int i=1;i<=siz[u]*2;i++) pw[i]=1ll*pw[i1]*base%hshmod; dfs1(u,0),dfs2(u,0,u); }
const int mod=998244353; int qpow(int a,int b){ int res=1; while(b){ if(b&1) res=1ll*res*a%mod; a=1ll*a*a%mod; b>>=1; } return res; } int fac[maxn]={1},rev[maxn]={1}; void ini(){ for(int i=1;i<maxn;i++) fac[i]=1ll*fac[i1]*i%mod; rev[maxn1]=qpow(fac[maxn1],mod2); for(int i=maxn2;i>=0;i) rev[i]=1ll*rev[i+1]*(i+1)%mod; }
int myhsh[4][maxn],ans[maxn]; int myehsh[4][maxn*2],eans[maxn*2]; void dfs3(int u,int father){ for(int i=head[u];i;i=nex[i]){ if(to[i]==father) continue; dfs3(to[i],u);
map<__int64,pii>mp; int son=0; for(int j=head[to[i]];j;j=nex[j]){ if(to[j]==u) continue; __int64 key=get64(myehsh[0][j],myehsh[1][j]); if(mp.find(key)!=mp.end()) mp[key].first++; else mp[key]=pii(1,eans[j]); son++; } eans[i]=fac[son]; for(auto it:mp){ eans[i]=1ll*eans[i]*rev[it.second.first]%mod; eans[i]=1ll*eans[i]*qpow(it.second.second,it.second.first)%mod; } } } void dfs4(int u,int father){ map<__int64,pii>mp; int son=0; for(int i=head[u];i;i=nex[i]) { __int64 key=get64(myehsh[0][i],myehsh[1][i]); if(mp.find(key)!=mp.end()) mp[key].first++; else mp[key]=pii(1,eans[i]); son++; } ans[u]=fac[son];
for(auto it:mp){ ans[u]=1ll*ans[u]*rev[it.second.first]%mod; ans[u]=1ll*ans[u]*qpow(it.second.second,it.second.first)%mod; }
for(int i=head[u];i;i=nex[i]){ if(to[i]==father) continue; __int64 key=get64(myehsh[0][i],myehsh[1][i]); int a=mp[key].first, x=eans[i]; eans[i^1]=1ll*ans[u]*a%mod*qpow(1ll*x*son%mod,mod2)%mod; dfs4(to[i],u); } }
int main(){ ini(); int times;scanf("%d",×); while(times){ tot=1; int n;scanf("%d",&n); for(int i=0;i<n1;i++){ int u,v;scanf("%d%d",&u,&v); addedge(u,v); } int b[]={3,5},p[]={1000000009,1000000009}; for(int i=0;i<2;i++) treehash(1,myhsh[i],myehsh[i],b[i],p[i]); dfs3(1,0),dfs4(1,0); map<__int64,int>mp; long long res=0; for(int i=1;i<=n;i++) { __int64 key=get64(myhsh[0][i],myhsh[1][i]); if(mp[key]==0) res+=ans[i]; mp[key]=1; } printf("%d\n",int(res%mod)); deltree(1,0),tot=1; } }
