Cod sursa(job #567748)

Utilizator popadanielpopadaniel popadaniel Data 30 martie 2011 13:38:03
Problema Arbore partial de cost minim Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.07 kb
#include<stdlib.h>
#include<fstream.h>
#define NM 200001
#define MM 400001
#define endl "\n"

ifstream in("apm.in");
ofstream out("apm.out");

struct muchie{int x,y,c;};
int m,n,L[NM];
muchie v[MM],h[NM];
void citire(){
int i;
in>>n>>m;
for(i=0;i<m;i++)
	in>>v[i].x>>v[i].y>>v[i].c;
}
int fcmp(void const *a,void const *b)
{
return ((muchie*)a)->c-((muchie*)b)->c;
}

int min(int x,int y){
if(x<y) return x;
return y;
}

int max(int x,int y){
if(x>y) return x;
return y;
}

int find(int x){
if(x==L[x]) return x;
return find(L[x]);
}
void Union(int x,int y){
int px=find(x);
int py=find(y);
if(px<py) L[py]=px;
else L[px]=py;
}

int main(){
int i,ms=0,j,ct=0;
citire();
qsort(v,m,sizeof(v[0]),fcmp);
for(i=1;i<=n;i++)L[i]=i;
i=0;
while(ms<n-1){
	int px,py;
	do{px=find(v[i].x);
		 py=find(v[i].y);
		 if(px==py) i++;
		 }while(px==py);
		 ct+=v[i].c;
		 h[ms]=v[i];
		 ms++;
	int a=max(px,py);
	int b=min(px,py);
		Union(b,a);
		}
	out<<ct<<endl<<n-1<<endl;
	for(i=0;i<n-1;i++)
	out<<h[i].x<<" "<<h[i].y<<endl;
	return 0;
	}