#include <cstdio>
#include <cstring>
#include <iostream>
#include <vector>
#include <algorithm>
#include <set>
#include <stack>
#include <queue>
#include <list>
//#include <windows.h>
//#include <conio.h>
#include <cstdlib>
#include <time.h>
#include <limits.h>
#include <string>
#include <math.h>
using namespace std;
#define forA(V,it) for (typeof(V.begin()) it=V.begin();it!=V.end();it++)
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define ll long long
#define ull unsigned ll
#define MOD 1000000007
#define INF (1<<31)-1
#define MINF -(1<<31)
#define vi vector <int>
#define vll vector <ll>
#define pii pair <int,int>
#define pll pair <ll,ll>
#define newl printf("\n")
#define DIM 1000000
int N,M,x[400005],y[400005],cost[400005],ans,i,ind[400005],gr[400005];
bool cmp(int i,int j){return cost[i]<cost[j];}
vector <int> sol;
int find(int x)
{
    for (;x!=gr[x];x=gr[x]);
    return x;
}
void unite(int x,int y)
{
    gr[x]=y;
}
int main()
{
    freopen("apm.in","r",stdin);
    freopen("apm.out","w",stdout);
    scanf("%d %d",&N,&M);
    for (i=1;i<=M;i++)
    {
        scanf("%d %d %d",&x[i],&y[i],&cost[i]);
        ind[i]=gr[i]=i;
    }
    sort(ind+1,ind+M+1,cmp);
    for (i=1;i<=M;i++)
    {
        int a=find(x[ind[i]]),b=find(y[ind[i]]);
        if (a!=b)
        {
            unite(a,b); ans+=cost[ind[i]];
            sol.pb(ind[i]);
        }
    }
    printf("%d\n%d\n",ans,N-1);
    for (i=0;i<N-1;i++) printf("%d %d\n",x[sol[i]],y[sol[i]]);
    return 0;
}