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

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

const int NMax = 2e5 + 5;
const int inf = 1e9;
typedef long long ll;

int N,M,costArb;
int lung[NMax];
bool inApm[NMax];

struct elem {
    int x,y,c;
    elem (int _x = 0,int _y = 0,int _c = 0) {
        x = _x;
        y = _y;
        c = _c;
    }
};
bool operator <(elem a,elem b) {
    return a.c > b.c;
}

vector<elem> v[NMax];
vector<elem> sol;

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

    for (int i=2;i<=N;++i) {
        lung[i] = inf;
    }
    lung[1] = 0;

    priority_queue<elem> Q;
    Q.push(elem(0,1,0));
    while (Q.size()) {
        elem e = Q.top();
        Q.pop();
        int nod = e.y;
        if (lung[nod] < e.c) {
            continue;
        }
        inApm[nod] = true;
        costArb += e.c;
        sol.push_back(e);

        for (int k=0;k < (int)v[nod].size();++k) {
            int next = v[nod][k].y, cost = v[nod][k].c;
            if (inApm[next] || lung[next] <= cost) {
                continue;
            }

            lung[next] = cost;
            Q.push(elem(nod,next,cost));
        }
    }

    out<<costArb<<'\n'<<sol.size()-1<<'\n';
    for (int k=1;k < (int)sol.size();++k) {
        out<<sol[k].x<<' '<<sol[k].y<<'\n';
    }

    in.close();out.close();
    return 0;
}