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#include <iostream>
#include <fstream>
#include <vector>
#include <bitset>
#include <stack>
using namespace std;
ifstream si("2sat.in");
ofstream so("2sat.out");
vector<int>g[100005];
vector<int>gt[100005];
bitset<100005>vaz;
bitset<100005>sol;
stack<int> ord;
int n;
bool ok=true;
int neg(int a)
{
if(a>n)
a-=n;
else
a+=n;
return a;
}
void adaug(int a,int b)
{
g[a].push_back(b);
gt[b].push_back(a);
}
void dfs1(int nod)
{
vaz[nod]=1;
int i,l=g[nod].size();
for(i=0;i<l;++i)
{
if(!vaz[g[nod][i]])
dfs1(g[nod][i]);
}
ord.push(nod);
}
void dfs2(int nod)
{
if(sol[nod])
{
ok=false;
return;
}
vaz[nod]=sol[nod]=0;
sol[neg(nod)]=1;
int i,l=gt[nod].size();
for(i=0;i<l;++i)
{
if(vaz[gt[nod][i]])
{
dfs2(gt[nod][i]);
}
}
}
int main()
{
int m;
si>>n>>m;
int i;
int a,b;
for(i=0;i<m;++i)
{
si>>a>>b;
if(a<0)
a=n-a;
if(b<0)
b=n-b;
adaug(neg(a),b);
adaug(neg(b),a);
}
for(i=1;i<=n+n;++i)
{
if(!vaz[i])
{
dfs1(i);
}
}
while(!ord.empty())
{
a=ord.top();
ord.pop();
if(vaz[a]&&vaz[neg(a)])
dfs2(a);
}
if(!ok)
so<<"-1\n";
else
{
for(i=1;i<=n;++i)
so<<sol[i]<<' ';
so<<'\n';
}
return 0;
}