#include <bits/stdc++.h>
using namespace std;
using LL = long long;
#define pb emplace_back
#define sz(a) int(a.size())

const int N = 1e5 + 5;
int n, m, fa[N], ans[N];
array<int, 3> dis[N];
vector<pair<int, int>> G[N];
vector<int> id, disc;

inline int askd(int x) {
  return lower_bound(disc.begin(), disc.end(), x) - disc.begin() + 1;
}

int tr[N];
void add(int x, int y) {
  for (; x <= sz(disc); x += x & -x) {
    tr[x] += y;
  }
}
int ask(int x) {
  int y = 0;
  for (; x; x -= x & -x) {
    y += tr[x];
  }
  return y;
}

void dij(int s, int id) {
  for (int i = 1; i <= n; ++i) {
    dis[i][id] = 1e9;
  }
  priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>> Q;
  Q.emplace(dis[s][id] = 0, s);
  while (sz(Q)) {
    auto i = Q.top();
    auto d = i.first;
    auto u = i.second;
    Q.pop();
    if (d != dis[u][id]) {
      continue;
    }
    for (auto j : G[u]) {
      auto v = j.first;
      auto w = j.second;
      if (dis[v][id] > d + w) {
        Q.emplace(dis[v][id] = d + w, v);
      }
    }
  }
}

#define cmp(o) [&](int u, int v) {\
  for (auto k : {o, 0, 1, 2}) {\
    if (dis[u][k] < dis[v][k]) {\
      return true;\
    }\
    if (dis[u][k] > dis[v][k]) {\
      return false;\
    }\
  }\
  return false;\
}

void cdq(int l, int r) {
  if (l == r) {
    return ;
  }
  int mid = (l + r) >> 1;
  cdq(l, mid), cdq(mid + 1, r);
  sort(id.begin() + l, id.begin() + mid + 1, cmp(1));
  sort(id.begin() + mid + 1, id.begin() + r + 1, cmp(1));
  for (int i = l, j = mid + 1; i <= mid || j <= r; ) {
    if (j > r || i <= mid && dis[id[i]][1] <= dis[id[j]][1]) {
      add(askd(dis[id[i++]][2]), 1);
    }else {
      ans[id[j]] += ask(askd(dis[id[j]][2])), ++j;
    }
  }
  for (int i = l; i <= mid; ++i) {
    add(askd(dis[id[i]][2]), -1);
  }
}

signed main() {
  cin.tie(0)->sync_with_stdio(0);
  cin >> n >> m;
  for (int i = 1; i <= m; ++i) {
    int u, v, w;
    cin >> u >> v >> w, G[u].pb(v, w), G[v].pb(u, w);
  }
  for (auto i : {0, 1, 2}) {
    dij(i + 1, i);
  }
  for (int i = 1; i <= n; ++i) {
    disc.pb(dis[i][2]);
  }
  sort(disc.begin(), disc.end());
  disc.erase(unique(disc.begin(), disc.end()), disc.end());
  {
    vector<int> t(n);
    iota(t.begin(), t.end(), 1);
    sort(t.begin(), t.end(), cmp(0));
    for (int i = 0, r = 0; i < sz(t); i = ++r) {
      fa[t[i]] = t[i], id.pb(t[i]);
      while (r + 1 < sz(t) && dis[t[r + 1]] == dis[t[i]]) {
        fa[t[++r]] = t[i];
      }
    }
  }
  cdq(0, sz(id) - 1);
  int res = 0;
  for (int i = 1; i <= n; ++i) {
    res += !ans[fa[i]];
  }
  cout << res << '\n';
  return 0;
}