Pagini recente » Cod sursa (job #1854478) | Cod sursa (job #456986) | Cod sursa (job #447363) | Cod sursa (job #2408407) | Cod sursa (job #1343781)
#include <iostream>
#include <fstream>
#include <cstring>
#include <queue>
#define nmax 200005
#define cost first
#define vecin second
#define inf 0x3f3f3f3f
using namespace std;
vector<pair<int,int> >g[nmax];
priority_queue<pair<int,int> >q;
int d[nmax],n,m,viz[nmax],t[nmax];
ifstream fin("apm.in");
ofstream fout("apm.out");
void citire()
{
fin>>n>>m;
int x,y,c;
for(int i=1;i<=m;i++)
{
fin>>x>>y>>c;
g[x].push_back(make_pair(c,y));
g[y].push_back(make_pair(c,x));
}
memset(d,inf,sizeof(d));
}
void prim()
{
int k;
d[1]=0;
q.push(make_pair(0,1));
while(!q.empty())
{
k=q.top().vecin;
q.pop();
viz[k]=1;
vector<pair<int,int> >::iterator ii;
for(ii=g[k].begin();ii!=g[k].end();++ii)
if(viz[ii->vecin]==0&&d[ii->vecin]>ii->cost)
{
d[ii->vecin]=ii->cost;
t[ii->vecin]=k;
q.push(make_pair(-ii->cost,ii->vecin));
}
}
}
void afisare()
{
int s=0;
for(int i=2;i<=n;i++)
if(d[i]!=inf)
s+=d[i];
fout<<s<<"\n"<<n-1<<"\n";
for(int i=2;i<=n;i++)
fout<<i<<" "<<t[i]<<"\n";
}
int main()
{
citire();
prim();
afisare();
return 0;
}