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#include <cstdio>
#include <algorithm>
#include <cmath>
#include <vector>
#include <set>
#include <queue>
#include <stack>
#include <fstream>
#include <iostream>
#include <cstring>
#include <iomanip>
#define NMax 200005
#define INF 0x3f3f3f3f
using namespace std;
set<pair<int,int> > H;
vector<pair<int,int> > vecini[NMax];
int dist[NMax],tata[NMax],viz[NMax];
int n,m,x,y,c;
void rezolva(){
int s = 0;
for(int i = 1; i <= n; ++i){
s += dist[i];
}
printf("%d\n",s);
printf("%d\n",n - 1);
for(int i = 2; i <= n; i++){
printf("%d %d\n",i,tata[i]);
}
}
void prim(int x0){
// memset(tata,0,sizeof(tata));
// memset(viz,0,sizeof(viz));
memset(dist,INF,sizeof(dist));
dist[x0] = 0;
H.insert(make_pair(0,x0));
while(!H.empty()){
int nod = (*H.begin()).second;
H.erase(*H.begin());
viz[nod] = 1;
for(int i = 0; i < vecini[nod].size(); ++i){
if(dist[vecini[nod][i].first] > vecini[nod][i].second && !viz[vecini[nod][i].first]){
dist[vecini[nod][i].first] = vecini[nod][i].second;
tata[vecini[nod][i].first] = nod;
H.insert(make_pair(dist[vecini[nod][i].first], vecini[nod][i].first));
}
}
}
rezolva();
}
int main()
{
freopen("apm.in","r",stdin);
freopen("apm.out","w",stdout);
scanf("%d%d",&n,&m);
for(int i = 0; i < m; ++i){
scanf("%d%d%d",&x,&y,&c);
vecini[x].push_back(make_pair(y,c));
vecini[y].push_back(make_pair(x,c));
}
prim(1);
return 0;
}