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#include <iostream>
#include <fstream>
#include <algorithm>
using namespace std;
ifstream f("apm.in");
ofstream g("apm.out");
struct muchie
{
int x, y, cost;
int viz=0;
} muc[200001];
int n, m;
int a[200001], b[200001];
void init()
{
for (int i=1; i<=n; i++)
{
a[i]=i;
b[i]=1;
}
}
int caut(int x)
{
int r=x;
while (a[x]!=x)
x=a[x];
while (r!=x)
{
int next=a[r];
a[r]=x;
r=next;
}
return x;
}
void reun(int x, int y)
{
int ty=caut(y);
int tx=caut(x);
if (b[ty]<b[tx])
{
a[ty]=tx;
b[ty]=b[tx];
}
else if (b[tx]<b[ty])
{
a[tx]=ty;
b[tx]=b[ty];
}
else
{
a[tx]=ty;
b[ty]++;
b[tx]=b[ty];
}
}
bool cmp(muchie a, muchie b)
{
return a.cost<b.cost;
}
void cit()
{
f>>n>>m;
for (int i=0; i<m; i++)
f>>muc[i].x>>muc[i].y>>muc[i].cost;
}
int krusk()
{
int c=0;
for (int i=0; i<m; i++)
{
if (caut(muc[i].x)!=caut(muc[i].y))
{
muc[i].viz=1;
c+=muc[i].cost;
reun(muc[i].x, muc[i].y);
}
}
return c;
}
void afis()
{
g<<krusk()<<'\n'<<n-1<<'\n';
for (int i=0; i<m; i++)
if (muc[i].viz)
g<<muc[i].x<<' '<<muc[i].y<<'\n';
}
int main()
{
cit();
init();
sort(muc, muc+m, cmp);
afis();
return 0;
}