結果
問題 | No.1207 グラフX |
ユーザー |
![]() |
提出日時 | 2020-08-30 13:12:15 |
言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 251 ms / 2,000 ms |
コード長 | 3,352 bytes |
コンパイル時間 | 2,492 ms |
コンパイル使用メモリ | 204,084 KB |
最終ジャッジ日時 | 2025-01-13 20:57:08 |
ジャッジサーバーID (参考情報) |
judge3 / judge5 |
(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 <bits/stdc++.h>using namespace std;using Int = long long;const char newl = '\n';template<typename T1,typename T2> inline void chmin(T1 &a,T2 b){if(a>b) a=b;}template<typename T1,typename T2> inline void chmax(T1 &a,T2 b){if(a<b) a=b;}template<typename T> void drop(const T &x){cout<<x<<endl;exit(0);}template<typename T=Int>vector<T> read(size_t n){vector<T> ts(n);for(size_t i=0;i<n;i++) cin>>ts[i];return ts;}template<typename T,T MOD = 1000000007>struct Mint{static constexpr T mod = MOD;T v;Mint():v(0){}Mint(signed v):v(v){}Mint(long long t){v=t%MOD;if(v<0) v+=MOD;}Mint pow(long long k){Mint res(1),tmp(v);while(k){if(k&1) res*=tmp;tmp*=tmp;k>>=1;}return res;}static Mint add_identity(){return Mint(0);}static Mint mul_identity(){return Mint(1);}Mint inv(){return pow(MOD-2);}Mint& operator+=(Mint a){v+=a.v;if(v>=MOD)v-=MOD;return *this;}Mint& operator-=(Mint a){v+=MOD-a.v;if(v>=MOD)v-=MOD;return *this;}Mint& operator*=(Mint a){v=1LL*v*a.v%MOD;return *this;}Mint& operator/=(Mint a){return (*this)*=a.inv();}Mint operator+(Mint a) const{return Mint(v)+=a;}Mint operator-(Mint a) const{return Mint(v)-=a;}Mint operator*(Mint a) const{return Mint(v)*=a;}Mint operator/(Mint a) const{return Mint(v)/=a;}Mint operator-() const{return v?Mint(MOD-v):Mint(v);}bool operator==(const Mint a)const{return v==a.v;}bool operator!=(const Mint a)const{return v!=a.v;}bool operator <(const Mint a)const{return v <a.v;}static Mint comb(long long n,Int k){Mint num(1),dom(1);for(Int i=0;i<k;i++){num*=Mint(n-i);dom*=Mint(i+1);}return num/dom;}};template<typename T,T MOD> constexpr T Mint<T, MOD>::mod;template<typename T,T MOD>ostream& operator<<(ostream &os,Mint<T, MOD> m){os<<m.v;return os;}struct UnionFind{Int num;vector<Int> rs,ps;UnionFind(){}UnionFind(Int n):num(n),rs(n,1),ps(n,0){iota(ps.begin(),ps.end(),0);}Int find(Int x){return (x==ps[x]?x:ps[x]=find(ps[x]));}bool same(Int x,Int y){return find(x)==find(y);}void unite(Int x,Int y){x=find(x);y=find(y);if(x==y) return;if(rs[x]<rs[y]) swap(x,y);rs[x]+=rs[y];ps[y]=x;num--;}Int size(Int x){return rs[find(x)];}Int count() const{return num;}};template<typename F>struct FixPoint : F{FixPoint(F&& f):F(forward<F>(f)){}template<typename... Args>decltype(auto) operator()(Args&&... args) const{return F::operator()(*this,forward<Args>(args)...);}};template<typename F>inline decltype(auto) MFP(F&& f){return FixPoint<F>{forward<F>(f)};}//INSERT ABOVE HEREsigned main(){cin.tie(0);ios::sync_with_stdio(0);Int n,m,x;cin>>n>>m>>x;UnionFind uf(n);using P = pair<Int, Int>;vector<vector<P>> G(n);for(Int i=0;i<m;i++){Int a,b,c;cin>>a>>b>>c;a--;b--;if(uf.same(a,b)) continue;uf.unite(a,b);G[a].emplace_back(b,c);G[b].emplace_back(a,c);}using M = Mint<Int>;M ans{0};MFP([&](auto dfs,Int v,Int p)->Int{Int res=1;for(auto[u,c]:G[v]){if(u==p) continue;Int tmp=dfs(u,v);res+=tmp;ans+=M(n-tmp)*M(tmp)*M(x).pow(c);}return res;})(0,-1);cout<<ans<<newl;return 0;}