#include <bits/stdc++.h>

using namespace std;
ifstream f("apm.in");
ofstream g("apm.out");
const int nMax = 200005;
struct Vals{
    int x, y, c;
};
Vals a[nMax], rec[nMax];
int tata[nMax];
inline bool cmp(const Vals &A, const Vals &B) {
    return A.c < B.c;
}
inline void Union(int x,int y) {
    tata[x] = y;
}
inline int Find(int x) {
    if(tata[x] != x) {
        tata[x] = Find(tata[x]);
    }
    return tata[x];
}
int main()
{
    int n, m;
    f >> n >> m;
    for(int i = 1; i <= n; i++) {
        tata[i] = i;
    }
    for(int i = 1; i <= m; i++) {
        f >> a[i].x >> a[i].y >> a[i].c;
    }
    sort(a + 1, a + m + 1, cmp);
    int cnt = 0, ans = 0;
    for(int i = 1; i <= m; i++) {
        int x = Find(a[i].x);
        int y = Find(a[i].y);
        if(x == y) {
            continue;
        }
        Union(x, y);
        ans += a[i].c;
        cnt++;
        rec[cnt].x = a[i].x;
        rec[cnt].y = a[i].y;
    }
    g << ans << "\n";
    g << cnt << "\n";
    for(int i = 1; i <= cnt; i++) {
        g << rec[i].x << " " << rec[i].y << "\n";
    }
    return 0;
}