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#include <fstream>
#include <vector>
#define nMax 200005
#define pb push_back
#define mkp make_pair
#define INF 1 << 30
using namespace std;
ifstream fin("apm.in");
ofstream fout("apm.out");
vector<pair<int, int> > G[nMax], Edge;
int n, m, Sol, k, poz[nMax], heap[nMax], vec[nMax], val[nMax];
void in_apm(int node)
{
for(vector<pair<int, int> >::iterator it=G[node].begin();it!=G[node].end();it++)
{
int fiu=it->first;
int cost=it->second;
val[fiu]=min(val[fiu], cost);
if(val[fiu]==cost)
vec[fiu]=node;
}
}
void read()
{
int a, b, c;
fin>>n>>m;
for(int i=1;i<=m;i++)
{
fin>>a>>b>>c;
G[a].pb(mkp(b, c));
G[b].pb(mkp(a, c));
}
}
void upDate(int pozi)
{
int po;
while(pozi/2>0)
{
po=pozi/2;
if(val[heap[po]]>val[heap[pozi]])
{
swap(poz[heap[po]], poz[heap[pozi]]);
swap(heap[po], heap[pozi]);
pozi=po;
}
else
break;
}
}
void downDate(int pozi)
{
int po;
while(pozi*2<=k)
{
po=pozi*2;
if(po+1<=k && val[heap[po+1]]<val[heap[po]])
po++;
if(val[heap[pozi]]>val[heap[po]])
{
swap(poz[heap[pozi]], poz[heap[po]]);
swap(heap[po], heap[pozi]);
pozi=po;
}
else
break;
}
}
int in_heap(int node)
{
heap[++k]=node;
poz[node]=k;
upDate(k);
}
int out_heap()
{
int node=heap[1];
swap(poz[heap[1]], poz[heap[k]]);
swap(heap[1], heap[k--]);
downDate(1);
poz[node]=0;
return node;
}
void solve()
{
for(int i=2;i<=n;i++)
val[i]=INF;
in_apm(1);
for(int i=2;i<=n;i++)
in_heap(i);
for(int i=2;i<=n;i++)
{
int node=out_heap();
in_apm(node);
Sol+=val[node];
Edge.pb(mkp(node, vec[node]));
for(vector<pair<int, int> >::iterator it=G[node].begin();it!=G[node].end();it++)
{
int fiu=it->first;
if(poz[fiu])
upDate(poz[fiu]);
}
}
}
void write()
{
fout<<Sol<<'\n'<<Edge.size()<<'\n';
for(vector<pair<int, int> >::iterator it=Edge.begin();it!=Edge.end();it++)
fout<<it->first<<" "<<it->second<<'\n';
}
int main()
{
read();
solve();
write();
}