Cod sursa(job #755327)

Utilizator SmarandaMaria Pandele Smaranda Data 5 iunie 2012 14:34:47
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.93 kb
#include <cstdio>
#include <queue>
#include <vector>
using namespace std;
vector <long> a[100005];
vector <long> :: iterator it;
long l[100005];
bool viz[100005];
int main () {
    long n,m,x,y,s,i,elem;
    queue<long> q;

    freopen ("bfs.in","r",stdin);
    freopen ("bfs.out","w",stdout);

    scanf("%ld%ld%ld",&n,&m,&s);
    for (i=1;i<=m;i++) {
        scanf("%ld%ld",&x,&y);
        a[x].push_back(y);
    }
    q.push(s);
    l[s]=0;
	viz[s]=1;
    while (!q.empty()) {
        x=q.front();
        for (it=a[x].begin();it!=a[x].end();++it)
            if (!viz[*it]) {
                elem=*it;
                viz[*it]=1;
                l[*it]=l[x]+1;
                q.push(*it);
            }
        q.pop();
    }
    for (i=1;i<=n;i++) {
		if (l[i]==0 && s!=i)
			printf("-1 ");
		else 
			if (s==i)
				printf("0 ");
			else
			printf("%ld ",l[i]);
    }
    printf("\n");
    return 0;
}