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#include <bits/stdc++.h>
using namespace std;
ifstream fin("apm.in");
ofstream fout("apm.out");
struct Edge
{
int u, v, weight;
Edge(int u, int v, int weight) : u(u), v(v), weight(weight)
{
}
bool operator<(const Edge &other)
{
return weight < other.weight;
}
};
struct DSU
{
vector<int> parent, sz;
DSU(int n)
{
parent.assign(n + 1, 0);
sz.assign(n + 1, 1);
for (int i = 1; i <= n; i++)
parent[i] = i;
}
int find(int a)
{
if (parent[a] == a)
return a;
return parent[a] = find(parent[a]);
}
void unite(int a, int b)
{
a = find(a);
b = find(b);
if (a == b)
return;
if (sz[a] > sz[b])
swap(a, b);
parent[a] = b;
}
};
int n, m, cost;
vector<Edge> edge_list, mst;
void read()
{
fin >> n >> m;
for (int i = 0; i < m; i++)
{
int x, y, c;
fin >> x >> y >> c;
edge_list.push_back(Edge(x, y, c));
}
}
void kruskal()
{
DSU dsu(n);
sort(edge_list.begin(), edge_list.end());
for (auto &edge : edge_list)
{
if (mst.size() == n - 1)
return;
if (dsu.find(edge.u) != dsu.find(edge.v))
{
dsu.unite(edge.u, edge.v);
cost += edge.weight;
mst.push_back(edge);
}
}
}
int main()
{
read();
kruskal();
fout << cost << '\n';
fout << mst.size() << '\n';
for (auto &e : mst)
fout << e.v << ' ' << e.u << '\n';
return 0;
}