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#include <bits/stdc++.h>
using namespace std;
ifstream fin("apm.in");
ofstream fout("apm.out");
const int MAXN = 200000;
int dag_root[MAXN + 1], dag_depth[MAXN + 1], dag_edges = 0;
int N, M;
vector<tuple<int,int,int> > edges;
vector<pair<int,int> > sol;
int cost;
void init() {
for(int i = 1; i <= N; ++i)
dag_root[i] = i;
}
void read() {
fin >> N >> M;
init();
int a, b, c;
while(M--) {
fin >> a >> b >> c;
edges.emplace_back(c, a, b);
}
sort(edges.begin(), edges.end(), std::less<tuple<int,int,int> >());
}
int dag_getRoot(int x) {
if(dag_root[x] == x)
return x;
return (dag_root[x] = dag_getRoot(dag_root[x]));
}
bool dag_unit(int x, int y) {
int rootX = dag_getRoot(x), rootY = dag_getRoot(y);
if(rootX == rootY) return false;
++dag_edges;
sol.emplace_back(x, y);
if(dag_depth[rootX] <= dag_depth[rootY]) {
dag_root[rootX] = rootY;
if (dag_depth[rootX] == dag_depth[rootY])
++dag_depth[rootY];
} else {
dag_root[rootY] = rootX;
}
return true;
}
void solve() {
int i = 0, a, b, c;
while(dag_edges != N - 1)
{
tie(c, a, b) = edges[i++];
if (dag_unit(a, b))
cost += c;
}
}
void print() {
fout << cost << '\n';
fout << N - 1 << '\n';
int a, b;
for(const auto& x : sol) {
tie(a, b) = x;
fout << a << ' ' << b << '\n';
}
}
int main()
{
read();
solve();
print();
fin.close();
fout.close();
return 0;
}