結果
問題 | No.1207 グラフX |
ユーザー |
👑 ![]() |
提出日時 | 2020-08-30 13:26:11 |
言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 368 ms / 2,000 ms |
コード長 | 5,574 bytes |
コンパイル時間 | 2,879 ms |
コンパイル使用メモリ | 203,336 KB |
最終ジャッジ日時 | 2025-01-13 21:10:03 |
ジャッジサーバーID (参考情報) |
judge3 / judge4 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 3 |
other | AC * 46 |
ソースコード
#define _USE_MATH_DEFINES#include <bits/stdc++.h>using namespace std;#define FOR(i,m,n) for(int i=(m);i<(n);++i)#define REP(i,n) FOR(i,0,n)#define ALL(v) (v).begin(),(v).end()using ll = long long;const int INF = 0x3f3f3f3f;const ll LINF = 0x3f3f3f3f3f3f3f3fLL;const double EPS = 1e-8;const int MOD = 1000000007;// const int MOD = 998244353;const int dy[] = {1, 0, -1, 0}, dx[] = {0, -1, 0, 1};const int dy8[] = {1, 1, 0, -1, -1, -1, 0, 1}, dx8[] = {0, -1, -1, -1, 0, 1, 1, 1};template <typename T, typename U> inline bool chmax(T &a, U b) { return a < b ? (a = b, true) : false; }template <typename T, typename U> inline bool chmin(T &a, U b) { return a > b ? (a = b, true) : false; }struct IOSetup {IOSetup() {cin.tie(nullptr);ios_base::sync_with_stdio(false);cout << fixed << setprecision(20);}} iosetup;int mod = MOD;struct ModInt {unsigned val;ModInt(): val(0) {}ModInt(ll x) : val(x >= 0 ? x % mod : x % mod + mod) {}ModInt pow(ll exponent) const {ModInt tmp = *this, res = 1;while (exponent > 0) {if (exponent & 1) res *= tmp;tmp *= tmp;exponent >>= 1;}return res;}ModInt &operator+=(const ModInt &x) { if((val += x.val) >= mod) val -= mod; return *this; }ModInt &operator-=(const ModInt &x) { if((val += mod - x.val) >= mod) val -= mod; return *this; }ModInt &operator*=(const ModInt &x) { val = static_cast<unsigned long long>(val) * x.val % mod; return *this; }ModInt &operator/=(const ModInt &x) {// assert(__gcd(static_cast<int>(x.val), mod) == 1);unsigned a = x.val, b = mod; int u = 1, v = 0;while (b) {unsigned tmp = a / b;swap(a -= tmp * b, b);swap(u -= tmp * v, v);}return *this *= u;}bool operator==(const ModInt &x) const { return val == x.val; }bool operator!=(const ModInt &x) const { return val != x.val; }bool operator<(const ModInt &x) const { return val < x.val; }bool operator<=(const ModInt &x) const { return val <= x.val; }bool operator>(const ModInt &x) const { return val > x.val; }bool operator>=(const ModInt &x) const { return val >= x.val; }ModInt &operator++() { if (++val == mod) val = 0; return *this; }ModInt operator++(int) { ModInt res = *this; ++*this; return res; }ModInt &operator--() { val = (val == 0 ? mod : val) - 1; return *this; }ModInt operator--(int) { ModInt res = *this; --*this; return res; }ModInt operator+() const { return *this; }ModInt operator-() const { return ModInt(val ? mod - val : 0); }ModInt operator+(const ModInt &x) const { return ModInt(*this) += x; }ModInt operator-(const ModInt &x) const { return ModInt(*this) -= x; }ModInt operator*(const ModInt &x) const { return ModInt(*this) *= x; }ModInt operator/(const ModInt &x) const { return ModInt(*this) /= x; }friend ostream &operator<<(ostream &os, const ModInt &x) { return os << x.val; }friend istream &operator>>(istream &is, ModInt &x) { ll val; is >> val; x = ModInt(val); return is; }};ModInt abs(const ModInt &x) { return x; }struct Combinatorics {int val; // "val!" and "mod" must be disjoint.vector<ModInt> fact, fact_inv, inv;Combinatorics(int val = 10000000) : val(val), fact(val + 1), fact_inv(val + 1), inv(val + 1) {fact[0] = 1;FOR(i, 1, val + 1) fact[i] = fact[i - 1] * i;fact_inv[val] = ModInt(1) / fact[val];for (int i = val; i > 0; --i) fact_inv[i - 1] = fact_inv[i] * i;FOR(i, 1, val + 1) inv[i] = fact[i - 1] * fact_inv[i];}ModInt nCk(int n, int k) const {if (n < 0 || n < k || k < 0) return ModInt(0);// assert(n <= val && k <= val);return fact[n] * fact_inv[k] * fact_inv[n - k];}ModInt nPk(int n, int k) const {if (n < 0 || n < k || k < 0) return ModInt(0);// assert(n <= val);return fact[n] * fact_inv[n - k];}ModInt nHk(int n, int k) const {if (n < 0 || k < 0) return ModInt(0);return k == 0 ? ModInt(1) : nCk(n + k - 1, k);}};struct UnionFind {UnionFind(int n) : data(n, -1) {}int root(int ver) { return data[ver] < 0 ? ver : data[ver] = root(data[ver]); }bool unite(int u, int v) {u = root(u);v = root(v);if (u == v) return false;if (data[u] > data[v]) swap(u, v);data[u] += data[v];data[v] = u;return true;}bool same(int u, int v) { return root(u) == root(v); }int size(int ver) { return -data[root(ver)]; }private:vector<int> data;};using CostType = int;struct Edge {int src, dst; CostType cost;Edge(int src, int dst, CostType cost = 0) : src(src), dst(dst), cost(cost) {}inline bool operator<(const Edge &x) const {return cost != x.cost ? cost < x.cost : dst != x.dst ? dst < x.dst : src < x.src;}inline bool operator<=(const Edge &x) const { return !(x < *this); }inline bool operator>(const Edge &x) const { return x < *this; }inline bool operator>=(const Edge &x) const { return !(*this < x); }};int main() {int n, m, x; cin >> n >> m >> x;UnionFind uf(n);vector<vector<Edge>> graph(n);while (m--) {int x, y, z; cin >> x >> y >> z; --x; --y;if (uf.unite(x, y)) {graph[x].emplace_back(x, y, z);graph[y].emplace_back(y, x, z);}}ModInt ans = 0;function<int(int, int)> dfs = [&](int par, int ver) {int sub = 1;for (const Edge &e : graph[ver]) {if (e.dst == par) continue;int d = dfs(ver, e.dst);ans += ModInt(x).pow(e.cost) * d * (n - d);sub += d;}return sub;};dfs(-1, 0);cout << ans << '\n';return 0;}