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#include <fstream>
#include <vector>
using namespace std;
ifstream cin("apm.in");
ofstream cout("apm.out");
const int DIM = 200001, INF = 10000;
vector<int> a[DIM], c[DIM];
struct afis
{
int nx, ny;
} af[DIM];
int h[DIM], d[DIM], poz[DIM], pred[DIM];
int nh, n, S, kt = 1;
void urca(int p);
void sterge(int p);
void coboara(int p);
void adauga(int val);
void prim(int x0);
int main()
{
int m;
cin >> n >> m;
for(int i = 1; i <= m; ++i)
{
int x, y, cost;
cin >> x >> y >> cost;
a[x].push_back(y);
a[y].push_back(x);
c[x].push_back(cost);
c[y].push_back(cost);
}
S = 0;
prim(1);
cout << S << '\n' << n - 1 << '\n';
for(int i = 1; i < n; ++i)
cout << af[i].nx << ' ' << af[i].ny << '\n';
return 0;
}
void prim(int x0)
{
int x;
for(int i = 1; i <= n; ++i)
{
d[i] = INF;
h[i] = i;
poz[i] = i;
}
d[x0] = 0;
urca(poz[x0]);
nh = n;
while(nh > 0)
{
x = h[1];
if(nh < n)
{
af[kt].nx = x;
af[kt].ny = pred[x];
kt++;
}
sterge(1);
for(int i = 0; i < a[x].size(); ++i)
{
int y = a[x][i];
int cost = c[x][i];
if(pred[x] != y && pred[y] != x && cost < d[y])
{
if(d[y] < INF)
S -= d[y];
d[y] = cost;
S += d[y];
pred[y] = x;
urca(poz[y]);
}
}
}
}
void urca(int p)
{
while(p > 1 && d[h[p]] < d[h[p / 2]])
{
swap(h[p], h[p / 2]);
poz[h[p]] = p;
poz[h[p / 2]] = p / 2;
p /= 2;
}
}
void coboara(int p)
{
int fs = p * 2, fd = p * 2 + 1, bun = p;
if(fs <= nh && d[h[fs]] < d[h[bun]])
{
bun = fs;
}
if(fd <= nh && d[h[fd]] < d[h[bun]])
{
bun = fd;
}
if(bun != p)
{
swap(h[bun], h[p]);
poz[h[p]] = p;
poz[h[bun]] = bun;
coboara(bun);
}
}
void adauga(int val)
{
h[++nh] = val;
urca(nh);
}
void sterge(int p)
{
swap(h[p], h[nh--]);
poz[h[p]] = p;
poz[h[nh + 1]] = nh + 1;
urca(p);
coboara(p);
}