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#include <iostream>
#include <fstream>
#include <queue>
#include <vector>
#include <climits>
#define NMAX 200002
using namespace std;
ifstream fin("apm.in");
ofstream fout("apm.out");
struct varf
{
int vf, c;
friend bool operator > (const varf &vf1, const varf &vf2);
};
bool operator > (const varf &vf1, const varf &vf2)
{
return vf1.c > vf2.c;
}
int n;
vector <varf> G[NMAX];
int cost_apm;
int cmin[NMAX];
int prec[NMAX];
int uz[NMAX];
priority_queue <varf, vector <varf>, greater<varf> > H;
void prim(int start)
{
int x, i, j, minim, vfmin;
varf aux;
for(x=1; x<=n; x++)
{
prec[x]=0;
cmin[x]=INT_MAX;
uz[x]=0;
}
cost_apm=0;
cmin[start]=0;
aux.vf=start;
aux.c=0;
H.push(aux);
for(j=1; j<=n; j++)
{
aux=H.top();
H.pop();
vfmin=aux.vf;
minim=aux.c;
if(!uz[vfmin])
{
uz[vfmin]=1;
cost_apm+=minim;
for(i=0; i<G[vfmin].size(); i++)
{
if(!uz[G[vfmin][i].vf] &&
cmin[G[vfmin][i].vf]>G[vfmin][i].c)
{
cmin[G[vfmin][i].vf]=G[vfmin][i].c;
prec[G[vfmin][i].vf]=vfmin;
aux.vf=G[vfmin][i].vf;
aux.c=cmin[G[vfmin][i].vf];
H.push(aux);
}
}
}
else
j--;
}
}
void afisare()
{
int x;
fout << cost_apm << '\n';
fout << n-1 << '\n';
for(x=1; x<=n; x++)
if(prec[x])
fout << x << ' ' << prec[x] << '\n';
}
void citire()
{
int i, m, x, y, cost;
varf v;
fin >> n >> m;
for(i=0; i<m; i++)
{
fin >> x >> y >> cost;
v.vf=y;
v.c=cost;
G[x].push_back(v);
v.vf=x;
G[y].push_back(v);
}
}
int main()
{
citire();
prim(1);
afisare();
return 0;
}