#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e5 + 10;
vector<pair<int, bool> > adj[maxn];
vector<pair<pair<int, int>, bool> > edge;
int dp[maxn], dis[maxn], par[maxn];
bool mark[maxn], in_path[maxn];
int n, m, ans = 0;
void input() {
  cin >> n >> m;
  for (int i = 0; i < m; i++) {
    int a, b, w;
    cin >> a >> b >> w;
    adj[a - 1].push_back(make_pair(b - 1, 1 - w));
    adj[b - 1].push_back(make_pair(a - 1, 1 - w));
    edge.push_back(make_pair(make_pair(a - 1, b - 1), 1 - w));
    if (w) ans++;
  }
}
void bfs() {
  queue<int> q;
  q.push(0);
  mark[0] = true;
  dis[0] = 0;
  dp[0] = 0;
  while (!q.empty()) {
    int v = q.front();
    q.pop();
    for (auto u : adj[v]) {
      if (!mark[u.first]) {
        q.push(u.first);
        mark[u.first] = true;
        dis[u.first] = dis[v] + 1;
        par[u.first] = v;
        dp[u.first] = dp[v] + u.second;
      } else if ((dp[u.first] > dp[v] + u.second) &&
                 (dis[u.first] == dis[v] + 1)) {
        par[u.first] = v;
        dp[u.first] = dp[v] + u.second;
      }
    }
  }
}
void check() {
  for (int i = 0; i < n; i++) cout << "par " << par[i] << endl;
}
void pp(int v) {
  if (par[v] == v) return;
  in_path[v] = true;
  pp(par[v]);
}
void output() {
  cout << ans - dis[n - 1] + 2 * dp[n - 1] << endl;
  in_path[0] = true;
  in_path[n - 1] = true;
  pp(n - 1);
  for (int i = 0; i < m; i++) {
    int a = edge[i].first.first, b = edge[i].first.second, w = edge[i].second;
    if (!in_path[a] || !in_path[b])
      if (!w) cout << a + 1 << " " << b + 1 << " " << w << endl;
    if (in_path[a] && in_path[b])
      if (w) cout << a + 1 << " " << b + 1 << " " << w << endl;
  }
  return;
}
int main() {
  input();
  bfs();
  output();
  return 0;
}
