#include <fstream>
#include <queue>
#include <bitset>

using namespace std;

const int N= 200001;
const int M= 400001;
const int INF = 1e9;

vector <pair<int,int>>a[N];
priority_queue <pair<int,int>> pq;

int d[N], pred[N], n,m,cost;
bitset <N> selectat;

void prim()
{
    for(int i=2; i<=n;i++)
    {
        d[i]=INF;
    }
    pq.push({0,1});
    while(!pq.empty())
    {
        int x=pq.top().second;
        pq.pop();
        if(selectat[x])
            continue;
        cost+=d[x];
        selectat[x]=true;
        for(auto p:a[x])
        {
            int y= p. first;
            int c= p.second;
            if(!selectat[y] && c<d[y])
            {
                d[y]=c;
                pred[y]=x;
                pq.push({-c,y});
            }
        }
    }
}

int main()
{
    ifstream in("apm.in");
    ofstream out("apm.out");
    in>>n>>m;
    for(int i=0;i<m;i++)
    {
        int x,y,c;
        in>>x>>y>>c;
        a[x].push_back({y,c});
        a[y].push_back({x,c});
    }
    prim();
    out<<cost<<"\n"<<n-1<<"\n";
    for(int i=2; i<=n;i++)
    {
        out<<i<<" "<<pred[i]<<"\n";
    }
    return 0;
}