結果
問題 | No.1207 グラフX |
ユーザー |
![]() |
提出日時 | 2020-08-30 13:14:32 |
言語 | C++11 (gcc 13.3.0) |
結果 |
AC
|
実行時間 | 291 ms / 2,000 ms |
コード長 | 2,243 bytes |
コンパイル時間 | 939 ms |
コンパイル使用メモリ | 93,392 KB |
実行使用メモリ | 36,292 KB |
最終ジャッジ日時 | 2024-11-15 06:30:54 |
合計ジャッジ時間 | 11,590 ms |
ジャッジサーバーID (参考情報) |
judge2 / judge4 |
(要ログイン)
ファイルパターン | 結果 |
---|---|
sample | AC * 3 |
other | AC * 46 |
ソースコード
#include <iostream>#include <cstdio>#include <cmath>#include <ctime>#include <cstdlib>#include <cassert>#include <vector>#include <list>#include <stack>#include <queue>#include <deque>#include <map>#include <set>#include <bitset>#include <string>#include <algorithm>#include <utility>#define llint long long#define inf 1e18#define rep(x, s, t) for(llint (x) = (s); (x) < (t); (x)++)#define Rep(x, s, t) for(llint (x) = (s); (x) <= (t); (x)++)#define chmin(x, y) (x) = min((x), (y))#define chmax(x, y) (x) = max((x), (y))#define mod 1000000007using namespace std;typedef pair<llint, llint> P;typedef pair<llint, P> E;struct UnionFind{int size;vector<int> parent;UnionFind(){}UnionFind(int size){this->size = size;parent.resize(size+1);init();}void init(){for(int i = 0; i <= size; i++) parent[i] = i;}int root(int i){if(parent[i] == i) return i;return parent[i] = root(parent[i]);}bool same(int i, int j){return root(i) == root(j);}void unite(int i, int j){int root_i = root(i), root_j = root(j);if(root_i == root_j) return;parent[root_i] = root_j;}};struct edge{llint to, cost;edge(){}edge(llint a, llint b){to = a, cost = b;}};llint modpow(llint a, llint n){if(n == 0) return 1;if(n % 2){return ((a%mod) * (modpow(a, n-1)%mod)) % mod;}else{return modpow((a*a)%mod, n/2) % mod;}}llint n, m, x;vector<edge> G[200005];vector<E> vec;UnionFind uf(200005);llint ans = 0;llint dfs(int v, int p){llint ret = 1;for(int i = 0; i < G[v].size(); i++){if(G[v][i].to == p) continue;llint res = dfs(G[v][i].to, v);ans += res * (n-res) % mod * modpow(x, G[v][i].cost) % mod;ans %= mod;ret += res;}return ret;}int main(void){ios::sync_with_stdio(0);cin.tie(0);cin >> n >> m >> x;llint u, v, w;for(int i = 1; i <= m; i++){cin >> u >> v >> w;vec.push_back(E(w, P(u, v)));}sort(vec.begin(), vec.end());for(int i = 0; i < vec.size(); i++){llint w = vec[i].first, u = vec[i].second.first, v = vec[i].second.second;if(uf.same(u, v)) continue;uf.unite(u, v);G[u].push_back(edge(v, w));G[v].push_back(edge(u, w));}dfs(1, -1);cout << ans << endl;return 0;}