#include<bits/stdc++.h>

using namespace std;

#define ll long long

#define C getchar()-48

inline ll read()

{

    ll s=0,r=1;

    char c=C;

    for(;c<0||c>9;c=C) if(c==-3) r=-1;

    for(;c>=0&&c<=9;c=C) s=(s<<3)+(s<<1)+c;

    return s*r;

}

const ll N=1e5+10,inf=1e18;

ll n,ans,mn=inf,zg;

ll c[N];

ll sz[N];

ll link[N],e[N<<1],nxt[N<<1],v[N<<1],top;

inline void llo(ll xx,ll yy,ll vv)

{

    e[++top]=yy,nxt[top]=link[xx],link[xx]=top,v[top]=vv;

}

inline void dfs(ll x,ll fa,ll deep)

{

    sz[x]=c[x];ans+=c[x]*deep;

    for(ll i=link[x];i;i=nxt[i])

    {

        ll u=e[i];

        if(u==fa) continue;

        dfs(u,x,deep+v[i]);

        sz[x]+=sz[u];

    }

}

inline void dfs2(ll x,ll fa,ll ans)

{

    mn=min(mn,ans);

    for(ll i=link[x];i;i=nxt[i])

    {

        ll u=e[i];

        if(u==fa) continue;

        dfs2(u,x,(ans+(zg-sz[u])*v[i]-(sz[u])*v[i]));

    }

}

int main()

{

    freopen("gather.in","r",stdin);

    freopen("gather.out","w",stdout);

    n=read();

    for(ll i=1;i<=n;i++) c[i]=read(),zg+=c[i];

    for(ll i=1;i<n;i++)

    {

        ll x=read(),y=read(),v=read();

        llo(x,y,v);llo(y,x,v);

    }

    dfs(1,0,0);

    dfs2(1,0,ans);

    cout<<mn;

    return 0;

}