#include <fstream>
#include <queue>
#include <vector>
#include <cstring>
using namespace std;
ifstream fin("apm.in");
ofstream fout("apm.out");

priority_queue<pair<int,int> >H;
vector<pair<int,int> >g[200001], arb;
int c[200001], x, y, cst, n, m, s, vec[200001];
bool vis[200001];

inline void Add(const int& node)
{
    for(vector<pair<int,int> >::iterator it=g[node].begin(); it<g[node].end(); it++ )
    {
        if(c[it->first]>it->second)
        {
            c[it->first]=it->second;
            vec[it->first]=node;
        }
        if(!vis[it->first])
            H.push(make_pair(-c[it->first],it->first));
    }
}

int main()
{
    fin>>n>>m;
    memset(c,0x3f3f3f3f,sizeof(c));
    for(int i = 1; i<= m; i++ )
    {
        fin>>x>>y>>cst;
        g[x].push_back(make_pair(y,cst));
        g[y].push_back(make_pair(x,cst));
    }
    c[1]=0;
    vis[1]=1;
    Add(1);
    for(int i = 1; i< n; i++ )
    {
        while(vis[H.top().second]) H.pop();
        int node = H.top().second;
        vis[node]=1;
        s+=c[node];
        arb.push_back(make_pair(node,vec[node]));
        Add(node);
    }
    fout<<s<<'\n' << arb.size()<<'\n';
    for(vector<pair<int,int> >::iterator it=arb.begin(); it<arb.end(); it++ )
        fout<<it->first<<' '<<it->second<<'\n';
    fin.close();
    fout.close();
    return 0;
}