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#include <iostream>
#include <fstream>
#include <vector>
#include <stack>
#include <bitset>
using namespace std;
ifstream si("2sat.in");
ofstream so("2sat.out");
vector<int> g[200005];
vector<int> gt[200005];
bitset<200005> v;
bitset<200005> sol;
stack<int> dr;
int n;
int neg(int x)
{
if(x<=n) return x+n;
else return x-n;
}
void add(int x,int y)
{
g[x].push_back(y);
gt[y].push_back(x);
}
bool ok=true;
void dfs1(int x)
{
v[x]=1;
int i,l=g[x].size();
for(i=0;i<l;++i)
{
if(!v[g[x][i]])
{
dfs1(g[x][i]);
}
}
dr.push(x);
}
void dfs2(int x)
{
if(sol[x])
{
ok=0;
return;
}
v[x]=sol[x]=0;
sol[neg(x)]=1;
int i,l=gt[x].size();
for(i=0;i<l;++i)
{
if(v[gt[x][i]])
{
dfs2(gt[x][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;
add(neg(a),b);
add(neg(b),a);
}
for(i=1;i<=n+n;++i)
{
if(!v[i])
dfs1(i);
}
while(!dr.empty())
{
a=dr.top();
dr.pop();
if(v[a]&&v[neg(a)])
dfs2(a);
}
if(!ok)
so<<-1<<'\n';
else
{
for(i=1;i<=n;++i)
so<<sol[i]<<' ';
}
return 0;
}