#include <iostream>
#include <climits>
#include <fstream>
#include <vector>
#include <queue>
#include <map>

using namespace std;
ifstream in("apm.in");
ofstream out("apm.out");

const int NMax = 2e5 + 5;
const int inf = 2e9;

struct elem {
    int x,y,val;
    elem() {
        elem(1,0);
    }
    elem(int a,int b) {
        y = a;
        val = b;
    }
    elem(int a,int b,int c) {
        x = a;
        y = b;
        val = c;
    }
};
vector<elem> v[NMax];

bool operator <(elem a,elem b) {
    return a.val>b.val;
}

int N,M,costArb;
int lung[NMax],pre[NMax];
bool inAPM[NMax];
priority_queue<elem> Q;
vector<elem> sol;

int main() {
    in>>N>>M;
    for (int i=1;i<=M;++i) {
        int x,y,c;
        in>>x>>y>>c;
        elem m1(y,c);
        v[x].push_back(m1);
        elem m2(x,c);
        v[y].push_back(m2);
    }

    for (int i=2;i<=N;++i) {
        lung[i] = inf;
    }
    lung[1] = 0;
    elem st(1,0);
    Q.push(st);
    while(Q.size()) {
        elem e = Q.top();
        Q.pop();
        if (lung[e.y] < e.val) {
            continue;
        }
        int nod = e.y;
        inAPM[nod] = true;
        costArb += e.val;
        elem s(pre[nod],nod,e.val);
        sol.push_back(s);

        vector<elem>::iterator it;
        for (it = v[nod].begin();it < v[nod].end();++it) {
            int next = it->y, cost = it->val;
            if (!inAPM[next] && lung[next] > cost) {
                lung[next] = cost;
                pre[next] = nod;
                elem n(next,cost);
                Q.push(n);
            }
        }
    }

    out<<costArb<<'\n'<<N-1<<'\n';
    for (int i=1;i<N;++i) {
        out<<sol[i].x<<' '<<sol[i].y<<'\n';
    }
    in.close();out.close();
    return 0;
}