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#include <bits/stdc++.h>
using namespace std;
ifstream fin("2sat.in");
ofstream fout("2sat.out");
int n,m;
vector<int> adj[200002];
vector<int> r_adj[200002];
bool visited[200002];
bool assigned[100002];
int norm(int x)
{
if(x<0)
return -x+n;
return x;
}
int neg(int x)
{
if(x>n)
return x-n;
return x+n;
}
vector<int> sortat;
vector<vector<int> >comp;
void dfs(int s, vector<int> *adjv, bool top,bool tare)
{
visited[s]=1;
for(int i=0 ; i<(int)adjv[s].size() ; i++)
{
int v=adjv[s][i];
if(visited[v]==0)
{
dfs(v,adjv,top,tare);
}
}
//cout<<s<<" ";
if (tare)
comp[comp.size()-1].push_back(s);
if(top)
sortat.push_back(s);
}
bool check()
{
for(int i=sortat.size()-1;i>=0;i--)
{
if(visited[sortat[i]]==0)
{
comp.push_back(vector<int>());
dfs(sortat[i],r_adj,0,1);
}
}
int saw[100002];
for(int i=0;i<comp.size();i++)
{
for(int j=0;j<comp[i].size();j++)
{
int x=comp[i][j];
if(x>n)
x=neg(x);
if(saw[x]==i+1)
return 1;
saw[x]=i+1;
}
}
return 0;
}
int main()
{
fin>>n>>m;
for(int i=0;i<m;i++)
{
int v1,v2;
fin>>v1>>v2;
v1=norm(v1),v2=norm(v2);
adj[neg(v1)].push_back(v2), r_adj[v2].push_back(neg(v1));
adj[neg(v2)].push_back(v1), r_adj[v1].push_back(neg(v2));
}
for(int i=2*n;i>0;i--)
{
if(visited[i]==0)
dfs(i,adj,1,0);
}
memset(visited, 0, (2*n+1)*sizeof(bool));
if(check())
{
fout<<-1;
return 0;
}
memset(visited, 0, (2*n+1)*sizeof(bool));
reverse(sortat.begin(),sortat.end());
for(int i=0;i<(int)sortat.size();i++)
{
int x=sortat[i];
if(sortat[i]>n)
x=neg(sortat[i]);
if(visited[x]==0)
{
visited[x]=1;
if(sortat[i]<=n)
assigned[x]=1;
}
}
for(int i=1;i<=n;i++)
fout<<assigned[i]<<" ";
return 0;
}