Cod sursa(job #538952)

Utilizator andreeabejenarubejenaru andreea andreeabejenaru Data 22 februarie 2011 09:44:56
Problema BFS - Parcurgere in latime Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 0.84 kb
#include<fstream.h>
#define NM 100001
ifstream in("dfs.in");
ofstream out("dfs.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;
}