Cod sursa(job #619471)
#include <stdio.h>
#include <vector>
#include <queue>
#define dim 100001
using namespace std;
vector <int> a[dim];
queue <int> q;
unsigned int n,m,s,c[dim];
bool v[dim];
void bfs()
{
unsigned int i,nod;
c[s]=1; //cost 1
q.push(s); //add start node to queue
while (!q.empty()) //queue not empty
{
nod = q.front();
v[nod] = true; //mark as visited
for (i=0;i<a[nod].size();i++)
if (v[a[nod][i]]==false) //not visited
{
c[a[nod][i]]=c[nod]+1; //calculate cost
q.push(a[nod][i]); //add in queue
}
q.pop(); //eliminate 1 element from queue
}
}
int main()
{
unsigned int i,x1,x2;
freopen("bfs.in","r",stdin);
freopen("bfs.out","w",stdout);
scanf("%d %d %d",&n,&m,&s);
s--;
for (i=0;i<m;i++)
{
scanf("%d %d",&x1,&x2);
a[x1-1].push_back(x2-1);
}
bfs();
printf("%d",c[0]-1);
for (i=1;i<n;i++)
printf(" %d",c[i]-1);
return 0;
}