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/**APM-Prim**/
#include<bits/stdc++.h>
using namespace std;
const int maxN=(2e5)+5;
int dp[maxN],pre[maxN];
set<pair<int,int> > q;
int n,m,x,y,z;
vector<pair<int,int> > edges,v[maxN];
const int inf=(1e9);
int sol;
bool seen[maxN],inSet[maxN];
int main()
{
freopen("apm.in","r",stdin);
freopen("apm.out","w",stdout);
scanf("%d%d",&n,&m);
for(int i=1;i<=m;i++)
{
scanf("%d%d%d",&x,&y,&z);
v[x].push_back(make_pair(y,z));
v[y].push_back(make_pair(x,z));
}
dp[1]=0;
for(int i=2;i<=n;i++)
dp[i]=inf;
q.insert(make_pair(0,1));
inSet[1]=1;
int nodes=0;
while(!q.empty())
{
int nod=(*q.begin()).second;
int cost=dp[nod];
q.erase(q.begin());
seen[nod]=1;
sol+=cost;
if(nod!=1)
edges.push_back(make_pair(pre[nod],nod));
for(auto it:v[nod])
{
int z=it.second;
if(seen[it.first]) continue;
if(dp[it.first]>z)
{
if(dp[it.first]!=inf) q.erase(q.find(make_pair(dp[it.first],it.first)));
pre[it.first]=nod;
dp[it.first]=z;
q.insert(make_pair(dp[it.first],it.first));
}
}
}
printf("%d\n",sol);
printf("%d\n",n-1);
for(auto it:edges)
printf("%d %d\n",it.first,it.second);
return 0;
}