#include <bits/stdc++.h>
#pragma GCC diagnostic ignored "-Wunused-result"
using namespace std;
template <class T>
using V = vector<T>;
template <class T>
using VV = vector<vector<T>>;
template <class T>
void _R(T &x) {
  cin >> x;
}
void _R(int &x) { scanf("%d", &x); }
void _R(int64_t &x) { scanf("%" PRId64, &x); }
void _R(double &x) { scanf("%lf", &x); }
void _R(char &x) { scanf(" %c", &x); }
void _R(char *x) { scanf("%s", x); }
void R() {}
template <class T, class... U>
void R(T &head, U &...tail) {
  _R(head);
  R(tail...);
}
template <class T>
void _W(const T &x) {
  cout << x;
}
void _W(const int &x) { printf("%d", x); }
void _W(const int64_t &x) { printf("%" PRId64, x); }
void _W(const double &x) { printf("%.16f\n", x); }
void _W(const char &x) { putchar(x); }
void _W(const char *x) { printf("%s", x); }
template <class T>
void _W(const vector<T> &x) {
  for (auto i = x.begin(); i != x.end(); _W(*i++))
    if (i != x.cbegin()) putchar(' ');
}
void W() {}
template <class T, class... U>
void W(const T &head, const U &...tail) {
  _W(head);
  putchar(sizeof...(tail) ? ' ' : '\n');
  W(tail...);
}
template <class T>
inline bool chmax(T &a, const T &b) {
  return b > a ? a = b, true : false;
}
template <class T>
inline bool chmin(T &a, const T &b) {
  return b < a ? a = b, true : false;
}
template <class T, class F = less<T>>
void sort_uniq(vector<T> &v, F f = F()) {
  sort(begin(v), end(v), f);
  v.resize(unique(begin(v), end(v)) - begin(v));
}
template <class T>
using MaxHeap = priority_queue<T>;
template <class T>
using MinHeap = priority_queue<T, vector<T>, greater<T>>;
using VI = V<int>;
const int N = 101, M = 1001, INF = 1e9;
int n, m;
vector<pair<int, int>> G[N];
vector<bool> used(M);
map<pair<int, int>, int> id;
void solve(int v) {
  MinHeap<pair<int, int>> q;
  VI dist(n, INF), parent(n, -1);
  dist[v] = 0;
  parent[v] = v;
  q.emplace(0, v);
  while (q.size()) {
    int u = q.top().second;
    int w = q.top().first;
    q.pop();
    if (w > dist[u]) continue;
    for (auto e : G[u]) {
      int to = e.first, c = e.second;
      if (dist[to] > dist[u] + c) {
        dist[to] = dist[u] + c;
        parent[to] = u;
        q.emplace(dist[to], to);
      }
    }
  }
  for (int i = 0; i < int(n); i++) {
    if (i == v) continue;
    int u = i;
    while (u != parent[u] && parent[u] != -1) {
      int p = parent[u];
      used[id[{min(u, p), max(u, p)}]] = true;
      u = p;
    }
  }
}
int main() {
  R(n, m);
  for (int i = 0; i < int(m); i++) {
    int a, b, c;
    R(a, b, c);
    --a;
    --b;
    G[a].push_back({b, c});
    G[b].push_back({a, c});
    id[{min(a, b), max(a, b)}] = i;
  }
  for (int i = 0; i < int(n); i++) solve(i);
  int ans = 0;
  for (int i = 0; i < int(m); i++)
    if (!used[i]) {
      cout << i << '\n';
      ans++;
    }
  W(ans);
  return 0;
}
