#include<cstdio>

 #include<algorithm>

 #define N 200010

 #define rg register

 #define LL long long

 using namespace std;

 int n,tot,last[N],v[N];

 LL ans,sum,size[N],dis[N];

 struct edge{

     int to,pre,dis;

 }e[N];

 inline int read(){

     int k=,f=; char c=getchar();

     while(c<''||c>'')c=='-'&&(f=-),c=getchar();

     while(''<=c&&c<='')k=k*+c-'',c=getchar();

     return k*f;

 }

 void dfs(int x,int fa){

     size[x]=v[x];

     for(rg int i=last[x],to;i;i=e[i].pre)if((to=e[i].to)!=fa){

         dis[to]=dis[x]+e[i].dis;

         dfs(to,x); size[x]+=size[to];

     }

 }

 void solve(int x,int fa,LL now){

     ans=min(ans,now);

     for(rg int i=last[x],to;i;i=e[i].pre)if((to=e[i].to)!=fa){

         LL tmp=now-size[to]*e[i].dis+(sum-size[to])*e[i].dis;

         solve(to,x,tmp);

     }

 }

 int main(){

     n=read();

     for(rg int i=;i<=n;i++) v[i]=read(),sum+=v[i];

     for(rg int i=;i<n;i++){

         int u=read(),v=read(),w=read();

         e[++tot]=(edge){v,last[u],w}; last[u]=tot;

         e[++tot]=(edge){u,last[v],w}; last[v]=tot;

     }

     dfs(,);

     for(rg int i=;i<=n;i++) ans+=dis[i]*v[i];

     solve(,,ans);

     printf("%lld\n",ans);

     return ;

 }