/**
    APM cu algoritmul Prim
**/
#include<bits/stdc++.h>
#define maxN 200005
#define INF INT_MAX
using namespace std;
int cost,n,dp[maxN],m[maxN],seen[maxN],x,y,c,muchii;
vector<pair<int,int> > v[maxN];
typedef struct edge
{
    int nod;
};
bool operator<(const edge& a,const edge& b)
{
    return dp[a.nod]>dp[b.nod];
}
priority_queue<edge> q;
void BuildAPM()
{
   int nodes=0;
    while(nodes<n)
    {
        while(!q.empty() && seen[q.top().nod]) q.pop();
      int  nod=q.top().nod;
        cost+=dp[nod];
        seen[nod]=1;
        nodes++;
        q.pop();
        for(vector<pair<int,int> >::iterator it=v[nod].begin();it!=v[nod].end();it++)
        {
            if(!seen[(*it).first] && dp[(*it).first]>(*it).second)
            {
                dp[(*it).first]=(*it).second;
                m[(*it).first]=nod;
               q.push({(*it).first});
            }
        }
    }
}
int main()
{
    freopen("apm.in","r",stdin);
    freopen("apm.out","w",stdout);
    scanf("%d%d",&n,&muchii);
    for(int i=1;i<=muchii;i++)
    {
        scanf("%d%d%d",&x,&y,&c);
        v[x].push_back(make_pair(y,c));
        v[y].push_back(make_pair(x,c));
    }
    for(int i=2;i<=n;i++) dp[i]=INF;
    q.push({1});
    BuildAPM();
    printf("%d\n",cost);
    printf("%d\n",n-1);
    for(int i=2;i<=n;i++)
    {
        printf("%d %d\n",m[i],i);
    }
    return 0;
}