#include <bits/stdc++.h>
#define inf 0x3f3f3f3f
using namespace std;

ifstream f("apm.in");
ofstream g("apm.out");

auto cmp = [] (pair<int,int> a, pair<int,int> b)
{
    return a.second > b.second;
};
priority_queue <pair<int,int>, vector<pair<int,int>>, decltype(cmp)> pq(cmp);
int n,m,i,x,y,a,b,pret,total,cost[200001],tata[200001];
vector <vector<pair<int,int>>> v;
bitset <200001> trecut;

int main()
{
    f >> n >> m;
    v.resize(n + 1);
    while(m --)
    {
        f >> x >> y >> pret;
        v[x].push_back({y,pret});
        v[y].push_back({x,pret});
    }
    for(i = 1; i <= n; ++ i)
        cost[i] = inf;
    for(i = 0; i < v[1].size(); ++ i)
    {
        a = v[1][i].first;
        b = v[1][i].second;
        cost[a] = b;
        tata[a] = 1;
        pq.push({a,b});
    }
    tata[1] = cost[1] = 0;
    trecut[1] = 1;
    while(!pq.empty())
    {
        a = pq.top().first;
        b = pq.top().second;
        pq.pop();
        if(trecut[a])
            continue;
        trecut[a] = 1;
        total += b;
        for(i = 0; i < v[a].size(); ++ i)
        {
            x = v[a][i].first;
            y = v[a][i].second;
            if(!trecut[x] && cost[x] > y)
            {
                cost[x] = y;
                tata[x] = a;
                pq.push({x,y});
            }
        }
    }
    g << total << '\n' << n - 1 << '\n';
    for(i = 2; i <= n; ++ i)
        g << i << ' ' << tata[i] << '\n';
}