#include<cstdio>

#include<cstring>

#include<algorithm>

#include<cctype>

#define ll long long

using namespace std;

const int maxn=;

struct edge{int v,w,from;}e[maxn*];//边数组开大！

int first[maxn],tot,size[maxn],n,a[maxn],N;

ll f[maxn],g[maxn],ans;

int read()

{

    char c;int s=,t=;

    while(!isdigit(c=getchar()))if(c=='-')t=-;

    do{s=s*+c-'';}while(isdigit(c=getchar()));

    return s*t;

}

void insert(int u,int v,int w)

{tot++;e[tot].v=v;e[tot].w=w;e[tot].from=first[u];first[u]=tot;}

void dfs1(int x,int fa){

    f[x]=;size[x]=a[x];

    for(int i=first[x];i;i=e[i].from)if(e[i].v!=fa){

        dfs1(e[i].v,x);

        size[x]+=size[e[i].v];

        g[e[i].v]=f[e[i].v]+1ll*size[e[i].v]*e[i].w;

        f[x]+=g[e[i].v];

    }

}

void dfs2(int x,int fa,ll num){

    ans=min(ans,num+f[x]);

    for(int i=first[x];i;i=e[i].from)if(e[i].v!=fa){

        dfs2(e[i].v,x,num+f[x]-g[e[i].v]+1ll*(N-size[e[i].v])*e[i].w);

    }

}

int main(){

    scanf("%d",&n);

    for(int i=;i<=n;i++)a[i]=read(),N+=a[i];

    int u,v,w;

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

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

        insert(u,v,w);insert(v,u,w);

    }

    dfs1(,-);

    ans=(1ll<<);

    dfs2(,-,);

    printf("%lld",ans);

    return ;

}