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#include <bits/stdc++.h>
using namespace std;
ifstream f("2sat.in");
ofstream g("2sat.out");
int n;
vector <int> v[100005],inv[100005];
int nod (int x)
{
if (x<0)
{
return n+abs(x);
}
return x;
}
void adauga(int x,int y)
{
x=nod(x),y=nod(y);
v[x].push_back(y);
inv[y].push_back(x);
}
int viz[100005],sal[400005],q;
void dfs(int x)
{
int i;
viz[x]=1;
for (i=0;i<v[x].size();i++)
{
int nod=v[x][i];
if (viz[nod]==0)
{
dfs(nod);
}
}
sal[++q]=x;
}
int nr;
vector <int> comp[400005];
void dfs2(int x)
{
int i;
comp[nr].push_back(x);
viz[x]=1;
for (i=0;i<inv[x].size();i++)
{
int nod=inv[x][i];
if (viz[nod]==0)
{
dfs2(nod);
}
}
}
int m,i,x,y,grupa[100005],val[100005],ok[100005],j;
int main()
{
f>>n>>m;
for (i=1;i<=m;i++)
{
f>>x>>y;
adauga(-x,y);
adauga(-y,x);
}
for (i=1;i<=n;i++)
{
if (viz[i]==0)
{
dfs(i);
}
}
nr=0;
memset(viz,0,sizeof(viz));
for (i=q;i>=1;i--)
{
if (viz[sal[i]]==0)
{
nr++;
dfs2(sal[i]);
}
}
for (i=1;i<=nr;i++)
{
for (int j=0;j<comp[i].size();j++)
{
grupa[comp[i][j]]=i;
}
}
for (i=1;i<=n;i++)
{
if (grupa[i]==grupa[i+n])
{
cout<<"-1"<<'\n';
return 0;
}
}
for (i=1;i<=n;i++)
{
if (ok[grupa[i]]==0)
{
ok[grupa[i]]=1;
ok[grupa[i+n]]=1;
for (j=0;j<comp[grupa[i]].size();j++)
{
int nod=comp[grupa[i]][j];
if (nod<=n)
{
val[nod]=1;
}
else
{
val[nod-n]=0;
}
}
}
}
for (i=1;i<=n;i++)
{
g<<val[i]<<" ";
}
return 0;
}