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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;
struct muchie
{
int x, y;
short cost;
} v[MAX_N + 1];
inline bool cmp(muchie a, muchie b)
{
if (a.cost > b.cost)
return 0;
return 1;
}
class DSU
{
private:
int n;
vector<int> t;
public:
// initializare
void init(int NMAX)
{
n = NMAX;
t.resize(n + 1);
for (int i = 1; i <= n; i++)
t[i] = i;
}
// radacina nodului x
int Find(int x)
{
if (t[x] == x)
return x;
return t[x] = Find(t[x]);
}
// reuniunea a doua multimi
void Union(int a, int b)
{
a = Find(a);
b = Find(b);
t[b] = a;
}
};
int n, m, k;
long long costMin;
vector<pair<int, int>> sol;
int main()
{
f >> n >> m;
for (int i = 0; i < m; i++)
f >> v[i].x >> v[i].y >> v[i].cost;
sort(v, v + m, cmp);
DSU s;
s.init(n);
for (int i = 0; i < m; i++)
if (s.Find(v[i].x) != s.Find(v[i].y))
{
costMin += v[i].cost;
sol.push_back({v[i].x, v[i].y});
s.Union(v[i].x, v[i].y);
}
g << costMin << '\n' << n - 1 << '\n';
for (int i = 0; i < n - 1; i++)
g << sol[i].first << ' ' << sol[i].second << '\n';
f.close();
g.close();
return 0;
}