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#include <bits/stdc++.h>
#define ll long long
using namespace std;
ifstream fin("apm.in");
ofstream fout("apm.out");
int n,m;
vector<vector<pair<int,int>>> adj;
void citire(){
fin >> n >> m;
adj.resize(n+1);
while(m--){
int x,y,c;
fin >> x >> y >> c;
adj[x].push_back({y, c});
adj[y].push_back({x,c});
}
}
void prim(int start){
priority_queue<pair<int,int>, vector<pair<int,int>>, greater<pair<int,int>>> pq;
vector<bool> viz(n+1, 0);
vector<int> parent(n+1, -1);
int ans = 0;
pq.push({0, start});
while(!pq.empty()){
pair<int,int> top = pq.top();
pq.pop();
int wt = top.first;
int u = top.second;
if(viz[u]) continue;
viz[u] = 1;
ans += wt;
for(auto v : adj[u]){
if(!viz[v.first]){
pq.push({v.second, v.first});
parent[v.first] = u;
}
}
}
fout << ans << '\n' << n-1 << '\n';
for(int i = 1; i<=n; i++){
if(parent[i] != -1) fout << parent[i] << ' ' << i << '\n';
}
}
int main(){
citire();
prim(1);
return 0;
}