#include <bits/stdc++.h>

using namespace std;
using ll = long long;
// #define int ll
using PII = pair<ll, ll>;

#define FOR(i, a, n) for (ll i = (ll)a; i < (ll)n; ++i)
#define REP(i, n) FOR(i, 0, n)
#define ALL(x) x.begin(), x.end()

template<typename T> T &chmin(T &a, const T &b) { return a = min(a, b); }
template<typename T> T &chmax(T &a, const T &b) { return a = max(a, b); }
template<typename T> bool IN(T a, T b, T x) { return a<=x&&x<b; }
template<typename T> T ceil(T a, T b) { return a/b + !!(a%b); }

template<typename T> vector<T> make_v(size_t a) { return vector<T>(a); }
template<typename T,typename... Ts>
auto make_v(size_t a,Ts... ts) {
  return vector<decltype(make_v<T>(ts...))>(a,make_v<T>(ts...));
}
template<typename T,typename V> typename enable_if<is_class<T>::value==0>::type
fill_v(T &t, const V &v) { t=v; }
template<typename T,typename V> typename enable_if<is_class<T>::value!=0>::type
fill_v(T &t, const V &v ) { for(auto &e:t) fill_v(e,v); }

template<class S,class T>
ostream &operator <<(ostream& out,const pair<S,T>& a){
  out<<'('<<a.first<<','<<a.second<<')'; return out;
}
template<typename T>
istream& operator >> (istream& is, vector<T>& vec){
  for(T& x: vec) {is >> x;} return is;
}
template<class T>
ostream &operator <<(ostream& out,const vector<T>& a){
  out<<'['; for(T i: a) {out<<i<<',';} out<<']'; return out;
}

int dx[] = {0, 1, 0, -1}, dy[] = {1, 0, -1, 0}; // DRUL
const int INF = 1<<30;
const ll LLINF = 1LL<<60;
const ll MOD = 1000000007;

struct UnionFind {
  vector<int> par, s;
  vector<ll> cost;
  UnionFind(int n=2e5) { init(n); }
  void init(int n) { 
    s.assign(n, 1); par.resize(n); 
    iota(par.begin(), par.end(), 0);
    cost.resize(n);
  }
  int find(int x) {
    if(par[x] == x) return x;
    return par[x] = find(par[x]);
  }
  void unite(int x, int y) {
    x = find(x);
    y = find(y);
    if(x == y) return;
    if(s[x] < s[y]) par[x] = y, s[y] = s[x] + s[y], cost[y] = cost[x] + cost[y];
    else par[y] = x, s[x] = s[x] + s[y], cost[x] = cost[x] + cost[y];
  }
  bool same(int x, int y) { return find(x) == find(y); }
  int size(int x) { return s[find(x)]; }
};

signed main(void) 
{
  cin.tie(0);
  ios::sync_with_stdio(false);

  ll n, m;
  cin >> n >> m;
  vector<ll> x(n);
  REP(i, n) cin >> x[i];
  vector<ll> a(m), b(m), c(m);
  REP(i, m) cin >> a[i] >> b[i] >> c[i], a[i]--, b[i]--;

  vector<ll> idx(m);
  iota(ALL(idx), 0);
  sort(ALL(idx), [&](ll l, ll r){
    return c[l] < c[r];
  });

  auto check = [&](ll mid) {
    UnionFind uf(n);
    REP(i, n) uf.cost[i] = x[i];
    // cout << uf.cost << endl;
    REP(i, mid) {
      if(uf.same(a[idx[i]], b[idx[i]])) continue;
      // cout << a[idx[i]] << " " << b[idx[i]] << endl;
      uf.unite(a[idx[i]], b[idx[i]]);
    }
    // REP(i, n) cout << uf.cost[i] << " ";
    // cout << endl;
    REP(i, mid) {
      if(c[idx[i]] > uf.cost[uf.find(a[idx[i]])]) return false;
    }
    return true;
  };

  ll lb = 0, ub = m;
  while(ub - lb > 1) {
    ll mid = (lb + ub) / 2;
    // cout << "lb=" << lb << " " << mid << " " << ub << endl;
    if(check(mid)) lb = mid;
    else ub = mid;
  }
  cout << m - lb << endl;

  return 0;
}