#pragma GCC optimize("O3") //#pragma GCC target("avx2") //#pragma GCC optimize("unroll-loops") #include using namespace std; typedef long long ll; typedef unsigned long long ull; typedef long double ld; typedef vector vi; typedef vector vll; typedef vector vld; typedef vector vb; typedef pair Pll; typedef pair Pin; ll INF = 1e16; int inf = 1e9; #define ALL(x) (x).begin(), (x).end() #define FOR(i, m, n) for (ll i = (m); i < (n); ++i) #define REVFOR(i, m, n) for (ll i = ((n) - 1); i >= (m); --i) #define REP(i, n) FOR(i, 0, n) #define REVREP(i, n) REVFOR(i, 0, n) #define fi first #define se second #define pb push_back #define mp make_pair #define eb emplace_back #define bcnt __builtin_popcountll // inputs #define VLLIN(x, n) vll x(n); REP(i, n) cin >> x[i]; #define VIIN(x, n) vin x(n); REP(i, n) cin >> x[i]; #define VLDIN(x, n) vld x(n); REP(i, n) cin >> x[i]; #define SIN(s, n) string s; cin >> s; #ifdef LOCAL #include #define debug(...) cerr << "[" << #__VA_ARGS__ << "]: ", d_err(__VA_ARGS__); #else #define debug(...) 83; #endif void d_err() { cerr << endl; } template void d_err(H h, T... t) { cerr << h << " "; d_err(t...); } template void print(T x) { cout << x << "\n"; } template void print(vector& x) { int N = x.size(); REP(i, N) { if (i > 0) cout << " "; cout << x[i]; } cout << "\n"; } //const ll MOD = 1000000007; const ll MOD = 998244353; struct mint { ll x; // typedef long long ll; mint(ll x=0):x((x%MOD+MOD)%MOD){} mint operator-() const { return mint(-x);} mint& operator+=(const mint a) { if ((x += a.x) >= MOD) x -= MOD; return *this; } mint& operator-=(const mint a) { if ((x += MOD-a.x) >= MOD) x -= MOD; return *this; } mint& operator*=(const mint a) { (x *= a.x) %= MOD; return *this; } mint operator+(const mint a) const { mint res(*this); return res+=a; } mint operator-(const mint a) const { mint res(*this); return res-=a; } mint operator*(const mint a) const { mint res(*this); return res*=a; } mint pow(ll t) const { if (!t) return 1; mint a = 1; mint tmp = *this; while(t > 0) { if (t & 1) a *= tmp; tmp *= tmp; t >>= 1; } return a; } // for prime MOD mint inv() const { return pow(MOD-2); } mint& operator/=(const mint a) { return (*this) *= a.inv(); } mint operator/(const mint a) const { return mint(*this) /= a; } }; istream& operator>>(istream& is, mint& a) { return is >> a.x;} ostream& operator<<(ostream& os, const mint& a) { return os << a.x;} typedef vector vmi; #define VMIIN(x, n) vmi x(n); REP(i, n) cin >> x[i]; int main(){ cin.tie(0); ios_base::sync_with_stdio(false); cout << fixed << setprecision(20); int n; cin >> n; vector edge(n); REP(i, n - 1) { int u, v; cin >> u >> v; u--, v--; edge[u].eb(v); edge[v].eb(u); } mint cnt = 0; auto dfs = [&](auto &&f, int cur, int par = -1) -> int { int ret = 1; for (auto &e: edge[cur]) { if (e == par) continue; int c1 = f(f, e, cur); ret += c1; cnt += c1 * (n - c1); } return ret; }; dfs(dfs, 0); mint ans = 1; mint all = n * (n - 1) / 2 * (n - 1); ans -= cnt / all; print(ans); }