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#include <cstdio>
#include <vector>
#include <queue>
#include <cstring>
#define nmax 200005
#define inf 0x3f3f3f3f
#define cost first
#define vecin second
using namespace std;
vector<pair<int,int> >g[nmax];
priority_queue<pair<int,int> >q;
int n,m,viz[nmax],t[nmax],d[nmax];
void citire()
{
int x,y,c;
scanf("%d%d",&n,&m);
for(int i=1;i<=m;i++)
{
scanf("%d%d%d",&x,&y,&c);
g[x].push_back(make_pair(c,y));
g[y].push_back(make_pair(c,x));
}
memset(d,inf,sizeof(d));
}
void prim()
{
int k;
q.push(make_pair(0,1));
d[1]=0;
while(!q.empty())
{
k=q.top().vecin;
q.pop();
viz[k]=1;
for(vector<pair<int,int> >::iterator ii=g[k].begin();ii!=g[k].end();++ii)
if(viz[ii->vecin]==0&&d[ii->vecin]>ii->cost)
{
d[ii->vecin]=ii->cost;
t[ii->vecin]=k;
q.push(make_pair(-d[ii->vecin],ii->vecin));
}
}
}
void afisare()
{
int s=0;
for(int i=2;i<=n;i++)
s+=d[i];
printf("%d\n%d\n",s,n-1);
for(int i=2;i<=n;i++)
printf("%d %d\n",t[i],i);
}
int main()
{
freopen("apm.in","r",stdin);
freopen("apm.out","w",stdout);
citire();
prim();
afisare();
return 0;
}