#include <cstdio>

#include <algorithm>

#include <vector>

#include <utility>

using namespace std;

const int N=100010;

typedef pair<int,int> P;

typedef long long LL;

vector<P> v[N];

int d[N],size[N],n;

LL ans,ans1;

void dfs(int x,int fx){

    for(int i=0;i<v[x].size();i++){

        int y=v[x][i].first,z=v[x][i].second;

        if(y!=fx){

            d[y]=d[x]+z;

            ans+=(LL)size[y]*d[y];

            dfs(y,x);

            size[x]+=size[y];

        }

    }

}

void dfs2(int x,int fx){

    for(int i=0;i<v[x].size();i++){

        int y=v[x][i].first,z=v[x][i].second;

        if(y!=fx){

            ans1+=(LL)(size[1]-2*size[y])*z;

            if(ans1<ans)ans=ans1;

            dfs2(y,x);

            ans1-=(LL)(size[1]-2*size[y])*z;

        }

    }

}

int main(){

    while(~scanf("%d",&n)){

        ans=ans1=0;

        for(int i=1;i<=n;i++)scanf("%d",&size[i]);

        for(int i=1;i<n;i++){

            int a,b,c;

            scanf("%d%d%d",&a,&b,&c);

            v[a].push_back(P(b,c));

            v[b].push_back(P(a,c));

        }dfs(1,-1);ans1=ans;

        dfs2(1,-1);

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

    }return 0;

}