#include <bits/stdc++.h>
using namespace std;
ifstream f("algola.in");
ofstream g("algola.out");
struct elem
{
    int nod, poz;
};
int cnt=0;
vector <elem> v[10009];
bool viz[10009];
int x[10009], y[10009], c[10009];
queue <int> q;
int s, d, sol=0, n;
elem tata[10009];
int N;
int val[10009];
int r[100009];
bool bfs ()
{
    for (int i=0; i<=N; i++)
        viz[i]=0, tata[i]= {-1, 0};
    q.push(s);
    viz[s]=1;
    while (!q.empty())
    {
        int x=q.front();
        q.pop();
        for (auto y:v[x])
        {
            if (!viz[y.nod] && r[y.poz]>0)
            {
                viz[y.nod]=1;
                tata[y.nod].nod=x;
                tata[y.nod].poz=y.poz;
                q.push(y.nod);
            }
        }
    }
    return viz[d];
}
void flux_maxim ()
{
    int flow=0;
    while (bfs())
    {
        for (auto y:v[d])
        {
            if ((tata[y.nod].nod!=0 || y.nod==s) && r[y.poz^1]>0)
            {
                flow=r[y.poz^1];
                for (int j=y.nod; j!=s; j=tata[j].nod)
                {
                    flow=min (flow, r[tata[j].poz]);
                    if (!flow)
                        break;
                }
                if (flow)
                {
                    r[y.poz^1]-=flow;
                    r[y.poz]+=flow;
                    for (int j=y.nod; j!=s; j=tata[j].nod)
                    {
                        r[tata[j].poz]-=flow;
                        r[tata[j].poz^1]+=flow;
                    }
                    sol+=flow;
                }
            }
        }
    }
}
signed main ()
{
    int m, sum=0, ans=-1, k=0;
    f >> n >> m;
    for (int i=1; i<=n; i++)
        f >> val[i], sum+=val[i];
    for (int i=1; i<=m; i++)
        f >> x[i] >> y[i] >> c[i];
    s=0;
    for (int i=1; i<=n; i++)
    {
        if (val[i])
        {
            r[k]=val[i];
            v[s].push_back({i, k});
            k++;
            v[i].push_back({s, k});
            r[k]=0;
            k++;
        }
    }
    for (int t=0; t<=n+sum; t++)
    {
        if (t)
        {
            for (int i=1; i<=n; i++)
            {
                r[k]=1e9;
                v[(t-1)*n+i].push_back({t*n+i, k});
                k++;
                r[k]=0;
                v[t*n+i].push_back({(t-1)*n+i, k});
                k++;
            }
            for (int i=1; i<=m; i++)
            {
                r[k]=c[i];
                v[(t-1)*n+x[i]].push_back({t*n+y[i], k});
                k++;
                r[k]=0;
                v[t*n+y[i]].push_back({(t-1)*n+x[i], k});
                k++;
                r[k]=c[i];
                v[(t-1)*n+y[i]].push_back({t*n+x[i], k});
                k++;
                r[k]=0;
                v[t*n+x[i]].push_back({(t-1)*n+y[i], k});
                k++;
            }
        }
        d=t*n+1;
        N=n+d;
        flux_maxim();
        if (sol==sum)
        {
            ans=t;
            break;
        }

    }
    //flux_maxim();
    g << ans;
}