#pragma GCC target("avx") #pragma GCC optimize("O3") #pragma GCC optimize("unroll-loops") #include // #include // #include // #include // using namespace __gnu_pbds; // #include // namespace multiprecisioninteger = boost::multiprecision; // using cint=multiprecisioninteger::cpp_int; using namespace std; using ll=long long; using datas=pair; using ddatas=pair; using tdata=pair; using vec=vector; using mat=vector; using pvec=vector; using pmat=vector; // using llset=tree,rb_tree_tag,tree_order_statistics_node_update>; #define For(i,a,b) for(i=a;i<(ll)b;++i) #define bFor(i,b,a) for(i=b,--i;i>=(ll)a;--i) #define rep(i,N) For(i,0,N) #define rep1(i,N) For(i,1,N) #define brep(i,N) bFor(i,N,0) #define brep1(i,N) bFor(i,N,1) #define all(v) (v).begin(),(v).end() #define allr(v) (v).rbegin(),(v).rend() #define vsort(v) sort(all(v)) #define vrsort(v) sort(allr(v)) #define uniq(v) vsort(v);(v).erase(unique(all(v)),(v).end()) #define endl "\n" #define popcount __builtin_popcountll #define eb emplace_back #define print(x) cout< ostream& operator<<(ostream& os,const pair& p){return os<<"("< ostream& operator<<(ostream& os,const vector& v){ os<<"{";bool f=false; for(auto& x:v){if(f)os<<",";os< ostream& operator<<(ostream& os,const set& v){ os<<"{";bool f=false; for(auto& x:v){if(f)os<<",";os< ostream& operator<<(ostream& os,const multiset& v){ os<<"{";bool f=false; for(auto& x:v){if(f)os<<",";os< ostream& operator<<(ostream& os,const map& v){ os<<"{";bool f=false; for(auto& x:v){if(f)os<<",";os< inline bool chmax(T& a,const T b){bool x=a inline bool chmin(T& a,const T b){bool x=a>b;if(x)a=b;return x;} #ifdef DEBUG void debugg(){cout<void debugg(const T& x,const Args&... args){cout<<" "<size;--i)modncrlistm[i-1]=modncrlistm[i]*i%mod; } return modncrlistp[n]*modncrlistm[r]%mod*modncrlistm[n-r]%mod; } ll modpow(ll a,ll n,const ll m=mod){ if(n<0)return 0; ll res=1; while(n>0){ if(n&1)res=res*a%m; a=a*a%m; n>>=1; } return res; } constexpr ll gcd(const ll a,const ll b) noexcept{return (!b)?abs(a):(a%b==0)?abs(b):gcd(b,a%b);} constexpr ll lcm(const ll a,const ll b) noexcept{return a/gcd(a,b)*b;} vec subtree; mat g; ll dfs(ll now,ll par){ for(auto x:g[now]){ if(par==x)continue; subtree[now]+=dfs(x,now); } return subtree[now]+=1; } ll N,M,K,H,W,A,B,C,D; string s,t; ll ans; int main(){ startupcpp(); // int codeforces;cin>>codeforces;while(codeforces--){ ll i,j=0; cin>>N; subtree.resize(N,0); g.resize(N); rep1(i,N){ ll a,b; cin>>a>>b; --a;--b; g[a].emplace_back(b); g[b].emplace_back(a); } dfs(0,-1); debug(subtree); rep1(i,N){ ans+=subtree[i]*(N-subtree[i])%mod; } ans%=mod; print((mod+1-moddevide(ans,N*(N-1)/2%mod*(N-1)%mod))%mod); // } }