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// Algoritmul lui Kruskal - O(M log M)
#include <iostream>
#include <fstream>
#include <algorithm>
#include <vector>
using namespace std;
ifstream f("apm.in");
ofstream g("apm.out");
const int MAX_N = 2e5, MAX_M = 4e5;
int n, m, t[MAX_N + 1], r[MAX_N + 1];
struct muchie
{
int x, y;
short cost;
} v[MAX_M + 1];
inline bool cmp(muchie a, muchie b)
{
if (a.cost > b.cost)
return 0;
return 1;
}
void Citire()
{
f >> n >> m;
for (int i = 1; i <= m; i++)
f >> v[i].x >> v[i].y >> v[i].cost;
f.close();
}
int Find(int x)
{
if (t[x] == 0)
return x;
return (t[x] = Find(t[x]));
}
void Union(int x, int y)
{
if (r[x] < r[y])
t[x] = y;
else
{
t[y] = x;
if (r[x] == r[y])
r[x]++;
}
}
void Kruskal()
{
sort(v + 1, v + m + 1, cmp);
vector<pair<int, int>> sol;
long long costMin = 0;
for (int i = 1; i <= m; i++)
{
int rx = Find(v[i].x);
int ry = Find(v[i].y);
if (rx != ry)
{
Union(rx, ry);
costMin += v[i].cost;
sol.push_back({v[i].x, v[i].y});
}
}
g << costMin << "\n" << sol.size() << "\n";
for (auto edge : sol)
g << edge.first << " " << edge.second << "\n";
g.close();
}
int main()
{
Citire();
Kruskal();
return 0;
}