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#include<cstdio>
#include<algorithm>
#include<cmath>
using namespace std;
FILE *fin = freopen("apm.in", "r", stdin);
FILE *fout = freopen("apm.out", "w", stdout);
const int NMax = 200000;
int N, M;
int lg[NMax + 1], father[NMax + 1];
struct point {int x, y, c;} v[2 * NMax + 1], edge[NMax + 1];
int Find(int x){
while (father[x] != x)
x = father[x];
return x;
}
void Union(int x, int y){
if (lg[x] > lg[y])
father[y] = x;
else
father[x] = y;
if (lg[x] == lg[y])
lg[x] ++;
}
bool cmp(point a, point b){
return a.c < b.c;
}
int main(){
scanf("%d%d", &N, &M);
for (int i = 1; i <= M; i++){
scanf("%d%d%d", &v[i].x, &v[i].y, &v[i].c);
}
sort (v + 1, v + 1 + M, cmp);
for (int i = 1; i <= N; i++)
father[i] = i,
lg[i] = 1;
int cnt = 0, X, Y, sum = 0;
for (int i = 1; i < N; i++){
X = Find(v[i].x);
Y = Find(v[i].y);
if (X != Y){
sum += v[i].c;
Union(X, Y);
edge[++cnt] = v[i];
}
}
printf("%d\n%d\n", sum, cnt);
for (int i = 1; i <= cnt; i++)
printf("%d %d\n", edge[i].x, edge[i].y);
}