#include <bits/stdc++.h>
 
using namespace std;
 
ifstream fin("apm.in");
ofstream fout("apm.out");
 
pair<int, int> ans[400005];
int n, m, k;
int total;
int t[400005], rg[400005];
 
struct Muchie {
	int x, y, c;
} v[400005];
 
void Union(int a, int b) {
    if(rg[a] > rg[b]) {
        t[b] = a;
    } else if(rg[a] < rg[b]) {
        t[a] = b;
    } else {
        t[a] = b;
        rg[b]++;
    }
}
 
int Find(int nod) {
    while(t[nod] != nod) {
    	nod = t[nod];
    }
    return nod;
}
 
bool cmp(Muchie A, Muchie B) {
    return A.c < B.c;
}
 
int main() {
    fin >> n >> m;
    for(int i = 1; i <= m; i++) {
    	fin >> v[i].x >> v[i].y >> v[i].c;
    }
    fin.close();
    sort(v + 1, v + m + 1, cmp);
    for(int i = 1; i <= n; i++) {
    	t[i] = i;
    	rg[i] = 1;
    }
    for(int i = 1; i <= m; i++) {
        int nod1 = Find(v[i].x);
        int nod2 = Find(v[i].y);
        if(nod1 != nod2) {
        	Union(nod1, nod2);
            ans[++k] = {v[i].x, v[i].y};
            total += v[i].c;
        }
    }
    fout << total << "\n";
    fout << n - 1 << "\n";
    for(int i = 1; i < n; i++) {
        fout << ans[i].first << " " << ans[i].second << "\n";
    }
    fout.close();
	return 0;
}