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#include<fstream>
#include<vector>
using namespace std;
ifstream fin("2sat.in");
ofstream fout("2sat.out");
int n,m,existaSol=1,sol[200001],viz[200001],parc[200001],k;
vector<int> v[200001],t[200001];
inline int non(int x)
{
return (x>n)?(x-n):x+n;
}
inline int ind(int x)
{
return (x>0)?x:n-x;
}
void citire()
{
int x,y;
fin>>n>>m;
for(int i=1;i<=m;i++)
{
fin>>x>>y;
v[non(ind(x))].push_back(ind(y));
v[non(ind(y))].push_back(ind(x));
t[ind(y)].push_back(non(ind(x)));
t[ind(x)].push_back(non(ind(y)));
}
}
void df(int nod)
{
viz[nod]=1;
for(int i=0;i<v[nod].size();i++)
{
if(!viz[v[nod][i]])
df(v[nod][i]);
}
parc[++k]=nod;
}
void dft(int nod)
{
viz[nod]=0;
if(sol[nod]==1)
existaSol=0;
sol[non(nod)]=1;
for(int i=0;i<t[nod].size();i++)
{
if(viz[t[nod][i]]==1)
dft(t[nod][i]);
}
}
void rezolva()
{
for(int i=1;i<=2*n;i++)
{
if(!viz[i])
df(i);
}
for(int i=k;i>0;i--)
{
if(viz[parc[i]]==1 && viz[non(parc[i])]==1)
dft(parc[i]);
}
}
int main()
{
citire();
rezolva();
if(!existaSol)
{
fout<<-1;
return 0;
}
for(int i=1;i<=n;i++)
fout<<sol[i]<<" ";
return 0;
}