Pagini recente » Cod sursa (job #2745614) | Cod sursa (job #3263548) | Cod sursa (job #1950100) | Cod sursa (job #298984) | Cod sursa (job #2694277)
// using disjoint set union
#include <stdio.h>
#include <bits/stdc++.h>
#define rep(i, n) for(int i = 0; i < (int)(n); i++)
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;
const int INF = 0x3f3f3f3f;
const int Nmax = 2e5+7;
int TT[Nmax];
struct edge {
int a,b,c;
} e[Nmax];
inline bool cmp(const edge &u, const edge &v) { return u.c < v.c; }
ifstream fin ("apm.in");
ofstream fout ("apm.out");
int root(int a) {
if (a == TT[a]) { return a; }
return TT[a] = root(TT[a]);
}
int main(void) {
// freopen("apm.in", "r", stdin);
std::ios_base::sync_with_stdio(false);
std::cin.tie(NULL);
int n, m;
fin >> n >> m;
rep(i, m) {
fin >> e[i].a >> e[i].b >> e[i].c;
}
sort(e, e+m, cmp);
rep(i, n+1) { TT[i] = i;}
int cost = 0;
vi res;
rep(i, m) {
if (root(e[i].a) != root(e[i].b)) {
TT[root(e[i].b)] = root(e[i].a);
cost += e[i].c;
res.push_back(i);
}
}
fout << cost << '\n';
fout << res.size() << '\n';
for(auto i: res) {
fout << e[i].a << " " << e[i].b << '\n';
}
return 0;
}