#include<stdlib.h>
#include<fstream.h>
#define NM 200001
#define MM 400001
#define endl"\n"

ifstream in("kruskal.in");
ofstream out("kruskal.out");
struct muchie{ int x,y,c;
						 };
int n,m,L[NM];
muchie v[MM],h[NM];

void citire(){
int i;
in>>n>>m;
for(i=0;i<m;i++) in>>v[i].x>>v[i].y>>v[i].c;
}

int fcmp(void const *a,void const *b){
return ((muchie*)a)->c-((muchie*)b)->c;
}

int main(){
int i,ms=0,j,ct=0;
citire();
qsort(v,m,sizeof(v[0]),fcmp);
for(i=1;i<=n;i++) L[i]=i;
i=0;
while(ms<n-1){  while(L[v[i].x]==L[v[i].y]) i++;
 h[ms]=v[i];
 ms++;
 ct=ct+v[i].c;

for(j=1;j<=n;j++)
if(L[j]==L[v[i].y]) L[j]=L[v[i].x];
						}

out<<ct<<endl<<n-1<<endl;;
for(i=0;i<n-1;i++) out<<h[i].x<<" "<<h[i].y<<endl;

return 0;
		}