#include using namespace std; #define rep(i, n) for(int i = 0; i < n; i++) #define rep2(i, x, n) for(int i = x; i <= n; i++) #define rep3(i, x, n) for(int i = x; i >= n; i--) #define each(e, v) for(auto &e: v) #define pb push_back #define eb emplace_back #define all(x) x.begin(), x.end() #define rall(x) x.rbegin(), x.rend() #define sz(x) (int)x.size() using ll = long long; using pii = pair; using pil = pair; using pli = pair; using pll = pair; //const int MOD = 1000000007; const int MOD = 998244353; const int inf = (1<<30)-1; const ll INF = (1LL<<60)-1; template bool chmax(T &x, const T &y) {return (x < y)? (x = y, true) : false;}; template bool chmin(T &x, const T &y) {return (x > y)? (x = y, true) : false;}; struct io_setup{ io_setup(){ ios_base::sync_with_stdio(false); cin.tie(NULL); cout << fixed << setprecision(15); } } io_setup; template struct Mod_Int{ int x; Mod_Int() : x(0) {} Mod_Int(long long y) : x(y >= 0 ? y % mod : (mod - (-y) % mod) % mod) {} Mod_Int &operator += (const Mod_Int &p){ if((x += p.x) >= mod) x -= mod; return *this; } Mod_Int &operator -= (const Mod_Int &p){ if((x += mod - p.x) >= mod) x -= mod; return *this; } Mod_Int &operator *= (const Mod_Int &p){ x = (int) (1LL * x * p.x % mod); return *this; } Mod_Int &operator /= (const Mod_Int &p){ *this *= p.inverse(); return *this; } Mod_Int &operator ++ () {return *this += Mod_Int(1);} Mod_Int operator ++ (int){ Mod_Int tmp = *this; ++*this; return tmp; } Mod_Int &operator -- () {return *this -= Mod_Int(1);} Mod_Int operator -- (int){ Mod_Int tmp = *this; --*this; return tmp; } Mod_Int operator - () const {return Mod_Int(-x);} Mod_Int operator + (const Mod_Int &p) const {return Mod_Int(*this) += p;} Mod_Int operator - (const Mod_Int &p) const {return Mod_Int(*this) -= p;} Mod_Int operator * (const Mod_Int &p) const {return Mod_Int(*this) *= p;} Mod_Int operator / (const Mod_Int &p) const {return Mod_Int(*this) /= p;} bool operator == (const Mod_Int &p) const {return x == p.x;} bool operator != (const Mod_Int &p) const {return x != p.x;} Mod_Int inverse() const{ assert(*this != Mod_Int(0)); return pow(mod-2); } Mod_Int pow(long long k) const{ Mod_Int now = *this, ret = 1; for(; k > 0; k >>= 1, now *= now){ if(k&1) ret *= now; } return ret; } friend ostream &operator << (ostream &os, const Mod_Int &p){ return os << p.x; } friend istream &operator >> (istream &is, Mod_Int &p){ long long a; is >> a; p = Mod_Int(a); return is; } }; using mint = Mod_Int; mint S = 0; mint M; template struct Graph{ struct edge{ int to, id; edge(int to, int id) : to(to), id(id) {} }; vector> es; const int n; int m; vector si; Graph(int n) : es(n), n(n), m(0), si(n) {} void add_edge(int from, int to){ es[from].emplace_back(to, m); if(!directed) es[to].emplace_back(from, m); m++; } mint dfs(int now, int pre = -1){ si[now] = 1; each(e, es[now]){ if(e.to == pre) continue; mint K = dfs(e.to, now); S += K*(M-K); si[now] += K; } return si[now]; } }; int main(){ int N; cin >> N; M = mint(N); Graph G(N); rep(i, N-1){ int u, v; cin >> u >> v; u--, v--; G.add_edge(u, v); } G.dfs(0); mint R = M*(M-1)*(M-1); //cout << S << ' ' << R << '\n'; cout << (R-S*2)/R << '\n'; }