Cod sursa(job #538930)

Utilizator val3kovidenie valentin val3k Data 22 februarie 2011 09:31:32
Problema BFS - Parcurgere in latime Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 0.83 kb
#include<fstream.h>
#define NM 1000//000

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

int c[NM],viz[NM],d[NM],n,m,start,li=1,ls;

struct nod{
int x;
nod *next;
};

nod *v[NM];
void add(nod *&l,int x){
nod *n=new (nod);
n->x=x;
n->next=l;
l=n;
}
int c_vida(){return ls<li;}

void pune(int x){c[++ls]=x;}
void scoate(int &x){x=c[li++];}

void build(){
int i,a,b;
in>>n>>m>>start;
for(i=1;i<=m;i++)
	in>>a>>b;
	add(v[a],b);
	}


void bf(int start){
int a,b;
nod *nc;
pune(start);viz[start]=1;
while(!c_vida()){
	scoate(a);
	nc=v[a];
	while(nc){
		b=nc->x;
		if(!viz[b]){
			pune(b);
			viz[b]=1;
			d[b]=d[a]+1;
			}
		nc=nc->next;
		}

	}
}
int main(){
int i;
build();
bf(start);
for(i=1;i<=n;i++)
	if(d[i]==0 && i!=start)
		d[i]=-1;
	for(i=1;i<=n;i++)
		out<<d[i]<<" ";
return 0;
}