#include <fstream>
#include <algorithm>

using namespace std;

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

int i, x, y, rx, ry, cost, t[400002], n, m, c, k;

int rad(int x)
{
    while(t[x] > 0)
        x = t[x];
    return x;
}

struct graf
{
    int x, y, c;
}arb[400002], sol[400002];

bool cmp (graf a, graf b)
{
    return a.c < b.c;
}

int main()
{
    f>>n>>m;
    for(int i = 1; i <= m; ++ i)
    {
        f>>x>>y>>c;
        arb[i].x = x;
        arb[i].y = y;
        arb[i].c = c;
    }

    sort(arb + 1, arb + m + 1, cmp);

    for(int i = 1; i <= n; ++ i)
        t[i] = -1;

    for(int i = 1; i <= m; ++ i)
    {
        x = arb[i].x;
        y = arb[i].y;
        rx = rad(x);
        ry = rad(y);
        if(rx == ry)
            continue;
        if(t[rx] < t[ry])
        {
            t[rx] += t[ry];
            t[ry] = rx;
        }
        else
        {
            t[ry] += t[rx];
            t[rx] = ry;
        }
        sol[++k].x = x;
        sol[k].y = y;
        cost += arb[i].c;
    }
    g<<cost<<'\n'<<k<<'\n';
    for(i = 1;i <= k; ++ i)
        g<<sol[i].x<<" "<<sol[i].y<<'\n';
    return 0;
}