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#include <fstream>
#include <vector>
#include <stack>
#include <set>
using namespace std;
ifstream fin ("2sat.in");
ofstream fout ("2sat.out");
set <int> r;
stack <int> s;
vector <int> l[200010];
int low[200010],niv[200010],w[200010];
int n,m,x,y,ok,g,i,j;
void dfs (int nod) {
niv[nod]=low[nod]=++g;
s.push(nod);
for (int i=0;i<l[nod].size();i++) {
if (niv[l[nod][i]]==0)
dfs(l[nod][i]);
if (niv[l[nod][i]]>0)
low[nod]=min(low[nod],low[l[nod][i]]);
}
if (low[nod]==niv[nod]) {
r.clear();
do {
x=s.top();
s.pop();
if ((x<=n && r.find(x+n)!=r.end()) || (x>n && r.find(x-n)!=r.end()))
ok=1;
r.insert(x);
if (w[x]==0){
w[x]=1;
if (x<=n)
w[x+n]=-1;
else
w[x-n]=-1;
}
niv[x]*=-1;
}while (x!=nod);
}
}
int main () {
fin>>n>>m;
for (i=1;i<=m;i++) {
fin>>x>>y;
if (x>0){
if (y>0) {
l[x+n].push_back(y);
l[y+n].push_back(x);
}else {
l[x+n].push_back(-y+n);
l[-y].push_back(x);
}
}else{
if (y>0) {
l[-x].push_back(y);
l[y+n].push_back(-x+n);
}else{
l[-x].push_back(-y+n);
l[-y].push_back(-x+n);
}
}
}
for (i=1;i<=2*n;i++)
if (niv[i]==0)
dfs(i);
if (ok)
fout<<"-1\n";
else
for (i=1;i<=n;i++)
fout<<(w[i]==1?1:0)<<" ";
return 0;
}