結果
| 問題 | No.1784 Not a star yet... |
| ユーザー |
 NyaanNyaan
|
| 提出日時 | 2021-11-23 23:05:03 |
| 言語 | C++17 (gcc 12.3.0 + boost 1.83.0) |
| 結果 |
WA
|
| 実行時間 | - |
| コード長 | 21,372 bytes |
| コンパイル時間 | 3,408 ms |
| コンパイル使用メモリ | 290,784 KB |
| 実行使用メモリ | 4,500 KB |
| 最終ジャッジ日時 | 2023-09-28 17:37:11 |
| 合計ジャッジ時間 | 8,579 ms |
|
ジャッジサーバーID （参考情報） |
judge13 / judge14 |
（要ログイン）
テストケース
テストケース表示| 入力 | 結果 | 実行時間 実行使用メモリ |
|---|---|---|
| testcase_00 | WA | - |
| testcase_01 | WA | - |
| testcase_02 | WA | - |
| testcase_03 | WA | - |
| testcase_04 | WA | - |
| testcase_05 | WA | - |
| testcase_06 | WA | - |
| testcase_07 | WA | - |
| testcase_08 | WA | - |
| testcase_09 | WA | - |
| testcase_10 | WA | - |
| testcase_11 | WA | - |
| testcase_12 | WA | - |
| testcase_13 | WA | - |
| testcase_14 | TLE | - |
| testcase_15 | -- | - |
| testcase_16 | -- | - |
| testcase_17 | -- | - |
| testcase_18 | -- | - |
| testcase_19 | -- | - |
| testcase_20 | -- | - |
| testcase_21 | -- | - |
| testcase_22 | -- | - |
| testcase_23 | -- | - |
| testcase_24 | -- | - |
| testcase_25 | -- | - |
| testcase_26 | -- | - |
| testcase_27 | -- | - |
| testcase_28 | -- | - |
| testcase_29 | -- | - |
| testcase_30 | -- | - |
| testcase_31 | -- | - |
| testcase_32 | -- | - |
| testcase_33 | -- | - |
| testcase_34 | -- | - |
| testcase_35 | -- | - |
| testcase_36 | -- | - |
| testcase_37 | -- | - |
| testcase_38 | -- | - |
| testcase_39 | -- | - |
| testcase_40 | -- | - |
| testcase_41 | -- | - |
| testcase_42 | -- | - |
| testcase_43 | -- | - |
| testcase_44 | -- | - |
| testcase_45 | -- | - |
| testcase_46 | -- | - |
| testcase_47 | -- | - |
| testcase_48 | -- | - |
| testcase_49 | -- | - |
| testcase_50 | -- | - |
| testcase_51 | -- | - |
| testcase_52 | -- | - |
| testcase_53 | -- | - |
| testcase_54 | -- | - |
| testcase_55 | -- | - |
| testcase_56 | -- | - |
| testcase_57 | -- | - |
| testcase_58 | -- | - |
| testcase_59 | -- | - |
| testcase_60 | -- | - |
| testcase_61 | -- | - |
| testcase_62 | -- | - |
| testcase_63 | -- | - |
ソースコード
/**
* date : 2021-11-23 23:04:51
*/
#define NDEBUG
using namespace std;
// intrinstic
#include <immintrin.h>
#include <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <cctype>
#include <cfenv>
#include <cfloat>
#include <chrono>
#include <cinttypes>
#include <climits>
#include <cmath>
#include <complex>
#include <cstdarg>
#include <cstddef>
#include <cstdint>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <deque>
#include <fstream>
#include <functional>
#include <initializer_list>
#include <iomanip>
#include <ios>
#include <iostream>
#include <istream>
#include <iterator>
#include <limits>
#include <list>
#include <map>
#include <memory>
#include <new>
#include <numeric>
#include <ostream>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <stack>
#include <streambuf>
#include <string>
#include <tuple>
#include <type_traits>
#include <typeinfo>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>
// utility
namespace Nyaan {
using ll = long long;
using i64 = long long;
using u64 = unsigned long long;
using i128 = __int128_t;
using u128 = __uint128_t;
template <typename T>
using V = vector<T>;
template <typename T>
using VV = vector<vector<T>>;
using vi = vector<int>;
using vl = vector<long long>;
using vd = V<double>;
using vs = V<string>;
using vvi = vector<vector<int>>;
using vvl = vector<vector<long long>>;
template <typename T, typename U>
struct P : pair<T, U> {
template <typename... Args>
P(Args... args) : pair<T, U>(args...) {}
using pair<T, U>::first;
using pair<T, U>::second;
T &x() { return first; }
const T &x() const { return first; }
U &y() { return second; }
const U &y() const { return second; }
P &operator+=(const P &r) {
first += r.first;
second += r.second;
return *this;
}
P &operator-=(const P &r) {
first -= r.first;
second -= r.second;
return *this;
}
P &operator*=(const P &r) {
first *= r.first;
second *= r.second;
return *this;
}
P operator+(const P &r) const { return P(*this) += r; }
P operator-(const P &r) const { return P(*this) -= r; }
P operator*(const P &r) const { return P(*this) *= r; }
};
using pl = P<ll, ll>;
using pi = P<int, int>;
using vp = V<pl>;
constexpr int inf = 1001001001;
constexpr long long infLL = 4004004004004004004LL;
template <typename T>
int sz(const T &t) {
return t.size();
}
template <typename T, typename U>
inline bool amin(T &x, U y) {
return (y < x) ? (x = y, true) : false;
}
template <typename T, typename U>
inline bool amax(T &x, U y) {
return (x < y) ? (x = y, true) : false;
}
template <typename T>
inline T Max(const vector<T> &v) {
return *max_element(begin(v), end(v));
}
template <typename T>
inline T Min(const vector<T> &v) {
return *min_element(begin(v), end(v));
}
template <typename T>
inline long long Sum(const vector<T> &v) {
return accumulate(begin(v), end(v), 0LL);
}
template <typename T>
int lb(const vector<T> &v, const T &a) {
return lower_bound(begin(v), end(v), a) - begin(v);
}
template <typename T>
int ub(const vector<T> &v, const T &a) {
return upper_bound(begin(v), end(v), a) - begin(v);
}
constexpr long long TEN(int n) {
long long ret = 1, x = 10;
for (; n; x *= x, n >>= 1) ret *= (n & 1 ? x : 1);
return ret;
}
template <typename T, typename U>
pair<T, U> mkp(const T &t, const U &u) {
return make_pair(t, u);
}
template <typename T>
vector<T> mkrui(const vector<T> &v, bool rev = false) {
vector<T> ret(v.size() + 1);
if (rev) {
for (int i = int(v.size()) - 1; i >= 0; i--) ret[i] = v[i] + ret[i + 1];
} else {
for (int i = 0; i < int(v.size()); i++) ret[i + 1] = ret[i] + v[i];
}
return ret;
};
template <typename T>
vector<T> mkuni(const vector<T> &v) {
vector<T> ret(v);
sort(ret.begin(), ret.end());
ret.erase(unique(ret.begin(), ret.end()), ret.end());
return ret;
}
template <typename F>
vector<int> mkord(int N, F f) {
vector<int> ord(N);
iota(begin(ord), end(ord), 0);
sort(begin(ord), end(ord), f);
return ord;
}
template <typename T>
vector<int> mkinv(vector<T> &v) {
int max_val = *max_element(begin(v), end(v));
vector<int> inv(max_val + 1, -1);
for (int i = 0; i < (int)v.size(); i++) inv[v[i]] = i;
return inv;
}
} // namespace Nyaan
// bit operation
namespace Nyaan {
__attribute__((target("popcnt"))) inline int popcnt(const u64 &a) {
return _mm_popcnt_u64(a);
}
inline int lsb(const u64 &a) { return a ? __builtin_ctzll(a) : 64; }
inline int ctz(const u64 &a) { return a ? __builtin_ctzll(a) : 64; }
inline int msb(const u64 &a) { return a ? 63 - __builtin_clzll(a) : -1; }
template <typename T>
inline int gbit(const T &a, int i) {
return (a >> i) & 1;
}
template <typename T>
inline void sbit(T &a, int i, bool b) {
if (gbit(a, i) != b) a ^= T(1) << i;
}
constexpr long long PW(int n) { return 1LL << n; }
constexpr long long MSK(int n) { return (1LL << n) - 1; }
} // namespace Nyaan
// inout
namespace Nyaan {
template <typename T, typename U>
ostream &operator<<(ostream &os, const pair<T, U> &p) {
os << p.first << " " << p.second;
return os;
}
template <typename T, typename U>
istream &operator>>(istream &is, pair<T, U> &p) {
is >> p.first >> p.second;
return is;
}
template <typename T>
ostream &operator<<(ostream &os, const vector<T> &v) {
int s = (int)v.size();
for (int i = 0; i < s; i++) os << (i ? " " : "") << v[i];
return os;
}
template <typename T>
istream &operator>>(istream &is, vector<T> &v) {
for (auto &x : v) is >> x;
return is;
}
void in() {}
template <typename T, class... U>
void in(T &t, U &... u) {
cin >> t;
in(u...);
}
void out() { cout << "\n"; }
template <typename T, class... U, char sep = ' '>
void out(const T &t, const U &... u) {
cout << t;
if (sizeof...(u)) cout << sep;
out(u...);
}
void outr() {}
template <typename T, class... U, char sep = ' '>
void outr(const T &t, const U &... u) {
cout << t;
outr(u...);
}
struct IoSetupNya {
IoSetupNya() {
cin.tie(nullptr);
ios::sync_with_stdio(false);
cout << fixed << setprecision(15);
cerr << fixed << setprecision(7);
}
} iosetupnya;
} // namespace Nyaan
// debug
namespace DebugImpl {
template <typename U, typename = void>
struct is_specialize : false_type {};
template <typename U>
struct is_specialize<
U, typename conditional<false, typename U::iterator, void>::type>
: true_type {};
template <typename U>
struct is_specialize<
U, typename conditional<false, decltype(U::first), void>::type>
: true_type {};
template <typename U>
struct is_specialize<U, enable_if_t<is_integral<U>::value, void>> : true_type {
};
void dump(const char& t) { cerr << t; }
void dump(const string& t) { cerr << t; }
void dump(const bool& t) { cerr << (t ? "true" : "false"); }
template <typename U,
enable_if_t<!is_specialize<U>::value, nullptr_t> = nullptr>
void dump(const U& t) {
cerr << t;
}
template <typename T>
void dump(const T& t, enable_if_t<is_integral<T>::value>* = nullptr) {
string res;
if (t == Nyaan::inf) res = "inf";
if constexpr (is_signed<T>::value) {
if (t == -Nyaan::inf) res = "-inf";
}
if constexpr (sizeof(T) == 8) {
if (t == Nyaan::infLL) res = "inf";
if constexpr (is_signed<T>::value) {
if (t == -Nyaan::infLL) res = "-inf";
}
}
if (res.empty()) res = to_string(t);
cerr << res;
}
template <typename T, typename U>
void dump(const pair<T, U>&);
template <typename T>
void dump(const pair<T*, int>&);
template <typename T>
void dump(const T& t,
enable_if_t<!is_void<typename T::iterator>::value>* = nullptr) {
cerr << "[ ";
for (auto it = t.begin(); it != t.end();) {
dump(*it);
cerr << (++it == t.end() ? "" : ", ");
}
cerr << " ]";
}
template <typename T, typename U>
void dump(const pair<T, U>& t) {
cerr << "( ";
dump(t.first);
cerr << ", ";
dump(t.second);
cerr << " )";
}
template <typename T>
void dump(const pair<T*, int>& t) {
cerr << "[ ";
for (int i = 0; i < t.second; i++) {
dump(t.first[i]);
cerr << (i == t.second - 1 ? "" : ", ");
}
cerr << " ]";
}
void trace() { cerr << endl; }
template <typename Head, typename... Tail>
void trace(Head&& head, Tail&&... tail) {
cerr << " ";
dump(head);
if (sizeof...(tail) != 0) cerr << ",";
trace(forward<Tail>(tail)...);
}
} // namespace DebugImpl
#ifdef NyaanDebug
#define trc(...) \
do { \
cerr << "## " << #__VA_ARGS__ << " = "; \
DebugImpl::trace(__VA_ARGS__); \
} while (0)
#else
#define trc(...) (void(0))
#endif
// macro
#define each(x, v) for (auto&& x : v)
#define each2(x, y, v) for (auto&& [x, y] : v)
#define all(v) (v).begin(), (v).end()
#define rep(i, N) for (long long i = 0; i < (long long)(N); i++)
#define repr(i, N) for (long long i = (long long)(N)-1; i >= 0; i--)
#define rep1(i, N) for (long long i = 1; i <= (long long)(N); i++)
#define repr1(i, N) for (long long i = (N); (long long)(i) > 0; i--)
#define reg(i, a, b) for (long long i = (a); i < (b); i++)
#define regr(i, a, b) for (long long i = (b)-1; i >= (a); i--)
#define fi first
#define se second
#define ini(...) \
int __VA_ARGS__; \
in(__VA_ARGS__)
#define inl(...) \
long long __VA_ARGS__; \
in(__VA_ARGS__)
#define ins(...) \
string __VA_ARGS__; \
in(__VA_ARGS__)
#define in2(s, t) \
for (int i = 0; i < (int)s.size(); i++) { \
in(s[i], t[i]); \
}
#define in3(s, t, u) \
for (int i = 0; i < (int)s.size(); i++) { \
in(s[i], t[i], u[i]); \
}
#define in4(s, t, u, v) \
for (int i = 0; i < (int)s.size(); i++) { \
in(s[i], t[i], u[i], v[i]); \
}
#define die(...) \
do { \
Nyaan::out(__VA_ARGS__); \
return; \
} while (0)
namespace Nyaan {
void solve();
}
int main() { Nyaan::solve(); }
//
template <typename T>
struct edge {
int src, to;
T cost;
edge(int _to, T _cost) : src(-1), to(_to), cost(_cost) {}
edge(int _src, int _to, T _cost) : src(_src), to(_to), cost(_cost) {}
edge &operator=(const int &x) {
to = x;
return *this;
}
operator int() const { return to; }
};
template <typename T>
using Edges = vector<edge<T>>;
template <typename T>
using WeightedGraph = vector<Edges<T>>;
using UnweightedGraph = vector<vector<int>>;
// Input of (Unweighted) Graph
UnweightedGraph graph(int N, int M = -1, bool is_directed = false,
bool is_1origin = true) {
UnweightedGraph g(N);
if (M == -1) M = N - 1;
for (int _ = 0; _ < M; _++) {
int x, y;
cin >> x >> y;
if (is_1origin) x--, y--;
g[x].push_back(y);
if (!is_directed) g[y].push_back(x);
}
return g;
}
// Input of Weighted Graph
template <typename T>
WeightedGraph<T> wgraph(int N, int M = -1, bool is_directed = false,
bool is_1origin = true) {
WeightedGraph<T> g(N);
if (M == -1) M = N - 1;
for (int _ = 0; _ < M; _++) {
int x, y;
cin >> x >> y;
T c;
cin >> c;
if (is_1origin) x--, y--;
g[x].emplace_back(x, y, c);
if (!is_directed) g[y].emplace_back(y, x, c);
}
return g;
}
// Input of Edges
template <typename T>
Edges<T> esgraph(int N, int M, int is_weighted = true, bool is_1origin = true) {
Edges<T> es;
for (int _ = 0; _ < M; _++) {
int x, y;
cin >> x >> y;
T c;
if (is_weighted)
cin >> c;
else
c = 1;
if (is_1origin) x--, y--;
es.emplace_back(x, y, c);
}
return es;
}
// Input of Adjacency Matrix
template <typename T>
vector<vector<T>> adjgraph(int N, int M, T INF, int is_weighted = true,
bool is_directed = false, bool is_1origin = true) {
vector<vector<T>> d(N, vector<T>(N, INF));
for (int _ = 0; _ < M; _++) {
int x, y;
cin >> x >> y;
T c;
if (is_weighted)
cin >> c;
else
c = 1;
if (is_1origin) x--, y--;
d[x][y] = c;
if (!is_directed) d[y][x] = c;
}
return d;
}
// 一般のグラフのstからの距離！！！！
// unvisited nodes : d = -1
vector<int> Depth(const UnweightedGraph &g, int start = 0) {
int n = g.size();
vector<int> ds(n, -1);
ds[start] = 0;
queue<int> q;
q.push(start);
while (!q.empty()) {
int c = q.front();
q.pop();
int dc = ds[c];
for (auto &d : g[c]) {
if (ds[d] == -1) {
ds[d] = dc + 1;
q.push(d);
}
}
}
return ds;
}
// Depth of Rooted Weighted Tree
// unvisited nodes : d = -1
template <typename T>
vector<T> Depth(const WeightedGraph<T> &g, int start = 0) {
vector<T> d(g.size(), -1);
auto dfs = [&](auto rec, int cur, T val, int par = -1) -> void {
d[cur] = val;
for (auto &dst : g[cur]) {
if (dst == par) continue;
rec(rec, dst, val + dst.cost, cur);
}
};
dfs(dfs, start, 0);
return d;
}
// Diameter of Tree
// return value : { {u, v}, length }
pair<pair<int, int>, int> Diameter(const UnweightedGraph &g) {
auto d = Depth(g, 0);
int u = max_element(begin(d), end(d)) - begin(d);
d = Depth(g, u);
int v = max_element(begin(d), end(d)) - begin(d);
return make_pair(make_pair(u, v), d[v]);
}
// Diameter of Weighted Tree
// return value : { {u, v}, length }
template <typename T>
pair<pair<int, int>, T> Diameter(const WeightedGraph<T> &g) {
auto d = Depth(g, 0);
int u = max_element(begin(d), end(d)) - begin(d);
d = Depth(g, u);
int v = max_element(begin(d), end(d)) - begin(d);
return make_pair(make_pair(u, v), d[v]);
}
// nodes on the path u-v ( O(N) )
template <typename G>
vector<int> Path(G &g, int u, int v) {
vector<int> ret;
int end = 0;
auto dfs = [&](auto rec, int cur, int par = -1) -> void {
ret.push_back(cur);
if (cur == v) {
end = 1;
return;
}
for (int dst : g[cur]) {
if (dst == par) continue;
rec(rec, dst, cur);
if (end) return;
}
if (end) return;
ret.pop_back();
};
dfs(dfs, u);
return ret;
}
ostream& operator<<(ostream& os, __int128_t x) {
if (x == 0) return os << 0;
if (x < 0) os << '-', x = -x;
string res;
while (x) res.push_back(x % 10 + '0'), x /= 10;
reverse(begin(res), end(res));
return os << res;
}
struct Rational {
using R = Rational;
using i128 = __int128_t;
// using i64 = long long;
// using u64 = unsigned long long;
using i64 = __int128_t;
using u64 = __uint128_t;
i64 x, y;
Rational() : x(0), y(1) {}
Rational(i64 _x, i64 _y = 1) : x(_x), y(_y) {
assert(y != 0);
if (_y != 1) {
i64 g = gcd(x, y);
if (g != 0) x /= g, y /= g;
if (y < 0) x = -x, y = -y;
}
}
u64 gcd(i64 A, i64 B) {
u64 a = A >= 0 ? A : -A;
u64 b = B >= 0 ? B : -B;
return __gcd(a, b);
/*
if (a == 0 || b == 0) return a + b;
int n = __builtin_ctzll(a);
int m = __builtin_ctzll(b);
a >>= n;
b >>= m;
while (a != b) {
int d = __builtin_ctzll(a - b);
bool f = a > b;
u64 c = f ? a : b;
b = f ? b : a;
a = (c - b) >> d;
}
return a << min(n, m);
*/
}
friend R operator+(const R& l, const R& r) {
return R(l.x * r.y + l.y * r.x, l.y * r.y);
}
friend R operator-(const R& l, const R& r) {
return R(l.x * r.y - l.y * r.x, l.y * r.y);
}
friend R operator*(const R& l, const R& r) { return R(l.x * r.x, l.y * r.y); }
friend R operator/(const R& l, const R& r) {
assert(r.x != 0);
return R(l.x * r.y, l.y * r.x);
}
R& operator+=(const R& r) { return (*this) = (*this) + r; }
R& operator-=(const R& r) { return (*this) = (*this) - r; }
R& operator*=(const R& r) { return (*this) = (*this) * r; }
R& operator/=(const R& r) { return (*this) = (*this) / r; }
R operator-() const {
R r;
r.x = -x, r.y = y;
return r;
}
R inverse() const {
assert(x != 0);
R r;
r.x = y, r.y = x;
if (x < 0) r.x = -r.x, r.y = -r.y;
return r;
}
R pow(long long p) const {
R res(1), base(*this);
while (p) {
if (p & 1) res *= base;
base *= base;
p >>= 1;
}
return res;
}
friend bool operator==(const R& l, const R& r) {
return l.x == r.x && l.y == r.y;
};
friend bool operator!=(const R& l, const R& r) {
return l.x != r.x || l.y != r.y;
};
friend bool operator<(const R& l, const R& r) {
return i128(l.x) * r.y < i128(l.y) * r.x;
};
friend bool operator<=(const R& l, const R& r) { return l < r || l == r; }
friend bool operator>(const R& l, const R& r) {
return i128(l.x) * r.y > i128(l.y) * r.x;
};
friend bool operator>=(const R& l, const R& r) { return l > r || l == r; }
friend ostream& operator<<(ostream& os, const R& r) {
os << r.x;
if (r.x != 0 && r.y != 1) os << "/" << r.y;
return os;
}
long long toMint(long long mod) {
assert(mod != 0);
i64 a = y, b = mod, u = 1, v = 0, t;
while (b > 0) {
t = a / b;
swap(a -= t * b, b);
swap(u -= t * v, v);
}
return i128((u % mod + mod) % mod) * x % mod;
}
};
template <typename R = Rational>
struct Binomial {
vector<R> fc;
Binomial(int = 0) { fc.emplace_back(1); }
void extend() {
int n = fc.size();
R nxt = fc.back() * n;
fc.push_back(nxt);
}
R fac(int n) {
while ((int)fc.size() <= n) extend();
return fc[n];
}
R finv(int n) { return fac(n).inverse(); }
R inv(int n) { return R{1, max(n, 1)}; }
R C(int n, int r) {
if (n < 0 or r < 0 or n < r) return R{0};
return fac(n) * finv(n - r) * finv(r);
}
R operator()(int n, int r) { return C(n, r); }
};
template <typename mint>
std::pair<int, mint> GaussElimination(vector<vector<mint>> &a,
int pivot_end = -1,
bool diagonalize = false) {
int H = a.size(), W = a[0].size();
int rank = 0, je = pivot_end;
if (je == -1) je = W;
mint det = 1;
for (int j = 0; j < je; j++) {
int idx = -1;
for (int i = rank; i < H; i++) {
if (a[i][j] != mint(0)) {
idx = i;
break;
}
}
if (idx == -1) {
det = 0;
continue;
}
if (rank != idx) {
det = -det;
swap(a[rank], a[idx]);
}
det *= a[rank][j];
if (diagonalize && a[rank][j] != mint(1)) {
mint coeff = a[rank][j].inverse();
for (int k = j; k < W; k++) a[rank][k] *= coeff;
}
int is = diagonalize ? 0 : rank + 1;
for (int i = is; i < H; i++) {
if (i == rank) continue;
if (a[i][j] != mint(0)) {
mint coeff = a[i][j] / a[rank][j];
for (int k = j; k < W; k++) a[i][k] -= a[rank][k] * coeff;
}
}
rank++;
}
return make_pair(rank, det);
}
template <typename mint>
vector<vector<mint>> LinearEquation(vector<vector<mint>> a, vector<mint> b) {
int H = a.size(), W = a[0].size();
for (int i = 0; i < H; i++) a[i].push_back(b[i]);
auto p = GaussElimination(a, W, true);
int rank = p.first;
for (int i = rank; i < H; ++i) {
if (a[i][W] != 0) return vector<vector<mint>>{};
}
vector<vector<mint>> res(1, vector<mint>(W));
vector<int> pivot(W, -1);
for (int i = 0, j = 0; i < rank; ++i) {
while (a[i][j] == 0) ++j;
res[0][j] = a[i][W], pivot[j] = i;
}
for (int j = 0; j < W; ++j) {
if (pivot[j] == -1) {
vector<mint> x(W);
x[j] = 1;
for (int k = 0; k < j; ++k) {
if (pivot[k] != -1) x[k] = -a[pivot[k]][j];
}
res.push_back(x);
}
}
return res;
}
using mint = Rational;
using namespace Nyaan;
void Nyaan::solve() {
inl(N);
map<int, int> ws;
Edges<ll> es;
rep(i, N - 1) {
inl(u, v, w);
--u, --v;
es.emplace_back(u, v, w);
ws[w]++;
}
int X = 0, Y = 0;
mint a = 0, b = 0;
tie(a, X) = *begin(ws);
if (sz(ws) == 2) tie(b, Y) = *next(begin(ws));
vector<vector<mint>> A((X + 1) * (Y + 1) - 1,
vector((X + 1) * (Y + 1), mint{}));
vector<mint> B((X + 1) * (Y + 1));
auto id = [&](int i, int j) { return i * (Y + 1) + j; };
rep(i, X + 1) rep(j, Y + 1) {
if (i == X and j == Y) continue;
mint p = N * (N - 1) / 2 - (X + Y - 1);
mint q = N - i - j;
if (i != 0) A[id(i, j)][id(i - 0, j)] += a * i * q;
if (i != 0) A[id(i, j)][id(i - 1, j)] += a * i * (p - q);
if (j != 0) A[id(i, j)][id(i, j - 0)] += b * j * q;
if (j != 0) A[id(i, j)][id(i, j - 1)] += b * j * (p - q);
if (i != X) A[id(i, j)][id(i + 0, j)] += a * (X - i) * (p - q + 1);
if (i != X) A[id(i, j)][id(i + 1, j)] += a * (X - i) * (q - 1);
if (j != Y) A[id(i, j)][id(i, j + 0)] += b * (Y - j) * (p - q + 1);
if (j != Y) A[id(i, j)][id(i, j + 1)] += b * (Y - j) * (q - 1);
mint all = (a * X + b * Y) * p;
A[id(i, j)][id(i, j)] -= all;
B[id(i, j)] = -all / N;
}
auto xs = LinearEquation(A, B)[0];
trc(LinearEquation(A, B));
rep(i, X + 1) rep(j, Y + 1) { trc(i, j, xs[id(i, j)]); }
vi cx(N), cy(N);
each(e, es) {
(a == e.cost ? cx : cy)[e.src]++;
(a == e.cost ? cx : cy)[e.to]++;
}
trc(cx, cy);
mint ans = 0;
rep(i, N) ans += xs[id(cx[i], cy[i])];
ans -= xs[id(1, 0)] * X + xs[id(0, 1)] * Y + xs[id(X, Y)];
//for(auto&r:xs)out(1.0*r.x/r.y);
//out(ans);
out(1.0 * ans.x / ans.y);
}