Pagini recente » Cod sursa (job #521338) | Cod sursa (job #147638) | Cod sursa (job #971412) | Cod sursa (job #3042243) | Cod sursa (job #2850652)
#include <bits/stdc++.h>
using namespace std;
ifstream fin("apm.in");
ofstream fout("apm.out");
const int dim=420000;
unsigned long long cost=0;
int ans=0;
int rang[250000];
struct muchie{
int x,y,c;
}g[dim];
struct pair{
int prim;
int secund;
}rez[dim];
int n,m;
int t[250000];
bool compara(muchie a,muchie b){
if (a.c<b.c) return 1;
return 0;
}
void citire()
{
fin>>n>>m;
for (int i=1;i<=m;i++)
{
fin>>g[i].x>>g[i].y>>g[i].c;
}
}
int radacina(int x)
{
if (t[x]==x) return x;
else{
while(t[x]!=x)
{
x=t[x];
}
}
return x;
}
void uneste(int a,int b)
{
if (rang[a]<rang[b]) t[a]=b;
if (rang[b]<rang[a]) t[b]=a;
if (rang[b]==rang[a])
{
rang[a]++;
t[a]=b;
}
}
void kruskal()
{
sort(g+1,g+1+m,compara);
for (int i=1;i<=n;i++) {
t[i]=i;
rang[i]=1;
}
for (int i=1;i<=m && ans<n;i++)
{
int a=radacina(g[i].x);
int b=radacina(g[i].y);
if (a!=b)
{
cost+=g[i].c;
rez[++ans].prim=g[i].x;
rez[ans].secund=g[i].y;
uneste(a,b);
}
}
fout<<cost<<'\n'<<n-1<<'\n';
for (int i=1;i<n;i++)
{
fout<<rez[i].prim<<' '<<rez[i].secund<<'\n';
}
}
int main()
{
citire();
kruskal();
}