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

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

#define ll long long
#define ull unsigned long long
#define pb push_back
const int inf = 1e9 + 5;
const int NMax = 2e5 + 5;

int N,M;
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],sol;

int main() {
    in>>N>>M;
    for (int i=1;i <= M;++i) {
        int x,y,c;
        in>>x>>y>>c;

        v[x].pb(elem(x,y,c));
        v[y].pb(elem(y,x,c));
    }

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

    int cost = 0;
    //int nrMuchii = 0;
    priority_queue<elem> Q;
    Q.push(elem(0,1,0));
    while (Q.size()) {
        elem e = Q.top();
        Q.pop();
        int node = e.y;

        if (inApm[node]) {
            continue;
        }
        inApm[node] = true;

        cost += e.c;
        //++nrMuchii;
        sol.pb(e);

        for (elem el : v[node]) {
            int nxt = el.y, cost = el.c;
            if (inApm[nxt] || lung[nxt] <= cost) {
                continue;
            }

            lung[nxt] = cost;
            Q.push(elem(node,nxt,cost));
        }
    }

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

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