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#include <fstream>
#include <vector>
#include <set>
using namespace std;
struct muchie {
int nod;
int cost;
bool operator <(const muchie& alt) const{
return this->cost < alt.cost;
}
};
const int N = 2e5, INF = 1 << 30;
vector<muchie> gr[N];
multiset<muchie> s;
int cmin[N], cor[N];
bool exista[N];
pair<int, int> rez[N];
void cost_minim(int nod) {
for (auto i : gr[nod])
if (!exista[i.nod] && i.cost < cmin[i.nod]) {
cmin[i.nod] = i.cost;
cor[i.nod] = nod;
s.insert(i);
}
}
int main() {
ifstream in("apm.in");
ofstream out("apm.out");
int n, m, x, y, c;
in >> n >> m;
while (m--) {
in >> x >> y >> c;
--x, --y;
gr[x].push_back({ y, c });
gr[y].push_back({ x, c });
}
for (int i = 0; i < N; ++i)
cmin[i] = INF;
cost_minim(0);
exista[0] = true;
int nod, cost, ctot = 0;
for (int i = 1; i < n; ++i) {
nod = s.begin()->nod;
while (exista[nod]) {
s.erase(s.begin());
nod = s.begin()->nod;
}
s.erase(s.begin());
exista[nod] = true;
cost = cmin[nod];
ctot += cost;
rez[i - 1] = { nod, cor[nod] };
cost_minim(nod);
}
out << ctot << '\n' << n - 1 << '\n';
for (int i = 0; i < n - 1; ++i)
out << rez[i].first + 1 << ' ' << rez[i].second + 1 << '\n';
in.close();
out.close();
return 0;
}