#include <bits/stdc++.h>
#define link pair<int, int>
#define x first
#define y second

using namespace std;
ifstream f("apm.in");
ofstream g("apm.out");
struct edge{
  int x, y, cost;
};


int n, m, x, y, z;
int rang[200001], t[200001];
vector<edge> edges;
vector<link> links;

int find(int x)
{
  if(t[x] == x)
    return x;
  return t[x] = find(t[x]);
}

void unite(int x, int y)
{
  if(t[x] == t[y])
    return;
  if(rang[x] < rang[y])
    rang[y] += rang[x], t[x] = y;
  else
    rang[x] += rang[y], t[y] = x;
}

bool comparer(edge e1, edge e2)
{
  return e1.cost < e2.cost;
}

void read()
{
  f>>n>>m;
  for(int i = 1;i <= m;++i)
    f>>x>>y>>z, edges.push_back({x, y, z});
  f.close();
}

void solve()
{
  sort(edges.begin(), edges.end(), comparer);

  for(int i = 1;i <= n;++i)
    t[i] = i, rang[i] = 1;
  long long cost = 0;

  for(auto it : edges)
    if(find(it.x) != find(it.y))
      {
        cost += it.cost;
        unite(find(it.x), find(it.y));
        links.push_back(make_pair(it.x, it.y));
      }
  g<<cost<<'\n';
  g<<links.size()<<'\n';
  for(auto it : links)
    g<<it.x<<" "<<it.y<<'\n';
  g.close();
}

int main()
{
  read();
  solve();
  return 0;
}