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#pragma comment(linker, "/STACK:1024000000")
#include <map>
#include <set>
#include <cmath>
#include <ctime>
#include <deque>
#include <queue>
#include <stack>
#include <vector>
#include <cstdio>
#include <string>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <algorithm>
using namespace std;
#define X first
#define Y second
#define pb push_back
#define mp make_pair
#define all(a) (a).begin(), (a).end()
#define fillchar(a, x) memset(a, x, sizeof(a))
#define copy(a, b) memcpy(a, b, sizeof(a))
typedef long long ll;
typedef pair<int, int> pii;
typedef unsigned long long ull;
//#ifndef ONLINE_JUDGE
void RI(vector<int>&a,int n){a.resize(n);for(int i=;i<n;i++)scanf("%d",&a[i]);}
void RI(){}void RI(int&X){scanf("%d",&X);}template<typename...R>
void RI(int&f,R&...r){RI(f);RI(r...);}void RI(int*p,int*q){int d=p<q?:-;
while(p!=q){scanf("%d",p);p+=d;}}void print(){cout<<endl;}template<typename T>
void print(const T t){cout<<t<<endl;}template<typename F,typename...R>
void print(const F f,const R...r){cout<<f<<", ";print(r...);}template<typename T>
void print(T*p, T*q){int d=p<q?:-;while(p!=q){cout<<*p<<", ";p+=d;}cout<<endl;}
//#endif
template<typename T>bool umax(T&a, const T&b){return b<=a?false:(a=b,true);}
template<typename T>bool umin(T&a, const T&b){return b>=a?false:(a=b,true);}
template<typename T>
void V2A(T a[],const vector<T>&b){for(int i=;i<b.size();i++)a[i]=b[i];}
template<typename T>
void A2V(vector<T>&a,const T b[]){for(int i=;i<a.size();i++)a[i]=b[i];}
#if 0
const double PI = acos(-1.0);
const int INF = 1e9 + 7;
const double EPS = 1e-8;
#endif
/* -------------------------------------------------------------------------------- */
const int maxn = 1e5 + ;
const int md = 1e9 + ;
struct Graph {
vector<vector<int> > G;
void clear() { G.clear(); }
void resize(int n) { G.resize(n + ); }
void add(int u, int v) { G[u].push_back(v); }
vector<int> & operator [] (int u) { return G[u]; }
};
Graph G;
bool vis[maxn];
int SZ[maxn], fac[maxn];
void pre_init() {
fac[] = ;
for (int i = ; i < maxn; i ++) fac[i] = (ll)fac[i - ] * i % md;
}
int dfs(int rt) {
vis[rt] = true;
SZ[rt] = ;
int cnt1 = , cnt2 = , ans = ;
for (int i = ; i < G[rt].size(); i ++) {
int v = G[rt][i];
if (!vis[v]) {
ans = (ll)ans * dfs(v) % md;
SZ[rt] += SZ[v];
if (SZ[v] <= ) cnt1 ++;
else cnt2 ++;
}
}
if (cnt2 > ) return ;
ans = (ll)ans * fac[cnt1] % md;
return cnt2? * ans % md : ans;
}
int main() {
#ifndef ONLINE_JUDGE
freopen("in.txt", "r", stdin);
//freopen("out.txt", "w", stdout);
#endif // ONLINE_JUDGE
int T, cas = , n, u, v;
pre_init();
cin >> T;
while (T --) {
cin >> n;
G.clear();
G.resize(n);
for (int i = ; i < n; i ++) {
scanf("%d%d", &u, &v);
G.add(u, v);
G.add(v, u);
}
fillchar(vis, );
fillchar(SZ, );
printf("Case #%d: %d\n", ++ cas, dfs() * (n >= ? : ) % md);
}
return ;
}
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