Pagini recente » Cod sursa (job #576074) | Cod sursa (job #1552485) | Cod sursa (job #143629) | Cod sursa (job #270988) | Cod sursa (job #2468537)
#include<fstream>
#include <bits/stdc++.h>
#include<vector>
#include<queue>
#define NM 200001
#define INF 2000000001
#include<stdio.h>
using namespace std;
ifstream f("apm.in");
ofstream g("apm.out");
int n, m, d[NM],viz[NM],t[NM];
long long ct;
struct pereche
{
int y,c;
};
struct compar
{
bool operator()(pereche p1,pereche p2)
{
return p1.c>p2.c;
}
};
vector<pereche> G[NM];
priority_queue <pereche, vector<pereche>, compar> q;
void Citeste()
{
int i, x,y;
pereche u;
f>>n>>m;
//fscanf(f,"%d %d",&n,&m);
for (i=1; i<=m; i++)
{
f>>x>>y>>u.c;
//fscanf(f,"%d %d %d",&x,&u.y,&u.c);
u.y=y;
G[x].push_back(u);
u.y=x;
G[y].push_back(u);
}
}
void Prim()
{
int z,lg,i,nr=0;
d[1]=0;
for (i=2; i<=n; i++)
d[i]=INF;
pereche p;
p.y=1;
p.c=0;
q.push(p);
while (!q.empty())
{
int j,im,y,c;
p=q.top();
q.pop();
im=p.y;
if(viz[im])
continue;
nr++;
viz[im]=1;
ct=ct+d[im];
for(j=0; j<G[im].size(); j++)
{
y=G[im][j].y;
c=G[im][j].c;
if(!viz[y] && c<=d[y])
{
t[y]=im;
d[y]=c;
q.push(G[im][j]);
}
}
}
}
void Scrie()
{
int i;
g<<ct<<'\n'<<n-1<<'\n';
for (i=2; i<=n; i++)
g<<i<<' '<<t[i]<<'\n';
}
int main()
{
Citeste();
Prim();
Scrie();
return 0;
}