#include #include using namespace std; using namespace atcoder; typedef long long int ll; typedef long double ld; #define FOR(i,l,r) for(ll i=l;i=l;i--) #define RREP(i,n) RFOR(i,0,n) #define ALL(x) x.begin(),x.end() #define PA pair #define F first #define S second #define BS(A,x) binary_search(ALL(A),x) #define LB(A,x) (ll)(lower_bound(ALL(A),x)-A.begin()) #define UB(A,x) (ll)(upper_bound(ALL(A),x)-A.begin()) #define COU(A,x) (UB(A,x)-LB(A,x)) #define sz(c) ((ll)(c).size()) //#include //namespace mp=boost::multiprecision; //using Bint=mp::cpp_int; templateusing min_priority_queue=priority_queue,greater>; templateostream&operator<<(ostream&os,pair&p){os<istream&operator>>(istream&is,pair&p){is>>p.F>>p.S;return is;} templateostream&operator<<(ostream&os,vector&v){REP(i,sz(v))os<istream&operator>>(istream&is,vector&v){for(T&in:v)is>>in;return is;} templatebool chmax(T&a,T b){if(abool chmin(T&a,T b){if(b>N; vector>E(N); REP(i,N-1){ ll u,v,w;cin>>u>>v>>w;u--;v--; E[u].emplace_back(PA(v,w)); E[v].emplace_back(PA(u,w)); } vectorD(N,1),cnt(N); queueQ; REP(i,N)cnt[i]=sz(E[i])-1;cnt[0]++; REP(i,N)if(!cnt[i])Q.emplace(i); while(sz(Q)){ ll v=Q.front();Q.pop(); for(auto[u,w]:E[v]){ D[u]+=D[v]; cnt[u]--; if(!cnt[u])Q.emplace(u); } } ll ans=0; REP(v,N)for(auto[u,w]:E[v])if(D[u]>D[v])ans+=w*D[v]*(N-D[v]); cout<