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#include <iostream>
#include <fstream>
#include <algorithm>
using namespace std;
ifstream fin("apm.in");
ofstream fout("apm.out");
int n, m, c, t[200001], k, rg[200001];
struct Muchie
{
int x, y, cost;
}v[400001], rez[200000];
bool Compare(Muchie a, Muchie b)
{
return a.cost < b.cost;
}
void input()
{
fin >> n >> m;
for(int i = 1; i <= m; ++i)
fin >> v[i].x >> v[i].y >> v[i].cost;
sort(v + 1, v + m + 1, Compare);
for(int i = 1; i <= n; ++i)
t[i] = -1, rg[i] = 1;
}
int find(int i)
{
if (t[i] == -1)
return i;
return t[i] = find(t[i]);
}
void unite(int x, int y)
{
int s1 = find(x);
int s2 = find(y);
if (s1 != s2)
{
if (rg[s1] < rg[s2])
{
t[s1] = s2;
rg[s2] += rg[s1];
}
else
{
t[s2] = s1;
rg[s1] += rg[s2];
}
}
}
void Solve()
{
/**bad time comlexity
int k = 0, i = 1;
while(k < n - 1)
{
int x = v[i].x, y = v[i].y;
if(t[x] != t[y])
{
c += v[i].cost;
rez[++ind].x = y, rez[ind].y = x;
int tx = t[x], ty = t[y];
for(int j = 1; j <= n; ++j)
if(t[j] == ty)
t[j] = tx;
k++;
}
i++;
}*/
int i;
for(i = 1, k = 0; i <= m && k < n - 1; ++i)
{
int x = find(v[i].x), y = find(v[i].y);
if(x != y)
{
c += v[i].cost;
rez[++k].x = v[i].x;
rez[k].y = v[i].y;
unite(v[i].x, v[i].y);
}
}
}
void output()
{
fout << c << '\n' << n - 1 << '\n';
for(int i = 1; i <= k; ++i)
fout << rez[i].x << ' ' << rez[i].y << '\n';
}
int main()
{
input();
Solve();
output();
return 0;
}