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#include<cstdio>
#include<algorithm>
#define MAX_N 200000
#define MAX_M 400000
using namespace std;
struct edge {
int x, y;
short cost;
};
struct APM {
int x, y;
};
edge v[MAX_M];
APM a[MAX_N];
int p[MAX_N + 1], h[MAX_N + 1], n, m, minCost, k;
inline bool cmp(edge a, edge b) {
return a.cost < b.cost;
}
void readGraph() {
FILE *fin = fopen("apm.in","r");
fscanf(fin,"%d%d",&n,&m);
for(int i = 0; i < m; i++)
fscanf(fin,"%d%d%hd",&v[i].x,&v[i].y,&v[i].cost);
fclose(fin);
}
void Init(int n) {
for(int i = 1; i <= n; i++) {
p[i] = i;
h[i] = 1;
}
}
inline int Find(int x) {
int tmp, aux;
aux = x;
while(p[aux] != aux)
aux = p[aux];
while(p[x] != aux) {
tmp = p[x];
p[x] = aux;
x = tmp;
}
return aux;
}
inline void Union(int x, int y, int i) {
int rootx, rooty;
rootx = Find(x);
rooty = Find(y);
if(rootx != rooty) {
minCost += v[i].cost;
a[k].x = x;
a[k++].y = y;
if(h[rootx] < h[rooty])
p[rootx] = rooty;
else if(h[rootx] > h[rooty])
p[rooty] = rootx;
else {
p[rootx] = rooty;
h[rooty]++;
}
}
}
void Kruskal() {
Init(n);
sort(v,v+m,cmp);
for(int i = 0; k < n - 1; i++)
Union(v[i].x,v[i].y,i);
}
void printAPM() {
FILE *fout = fopen("apm.out","w");
fprintf(fout,"%d\n%d\n",minCost,k);
for(int i = 0; i < k; i++)
fprintf(fout,"%d %d\n",a[i].x,a[i].y);
fclose(fout);
}
int main() {
readGraph();
Kruskal();
printAPM();
return 0;
}