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#include <iostream>
#include <fstream>
#include <vector>
using namespace std;
ifstream fin("2sat.in");
ofstream fout("2sat.out");
#define MAX 100010
typedef vector <int> :: iterator iter;
pair<int, int> e[2 * MAX];
vector <int> G[2 * MAX];
int viz[MAX], val[MAX], st[2 * MAX], dr;
#define viz (viz + MAX)
#define G (G + MAX)
#define val (val + MAX)
void df(int nod)
{
viz[nod] = 1;
for(iter it = G[nod].begin() ; it != G[nod].end() ; it++)
{
if(!viz[*it])
df(*it);
}
st[++dr] = nod;
}
int main()
{
int n, m, i, x, y, ok;
fin >> n >> m;
for(i = 1 ; i <= m ; i++)
{
fin >> e[i].first >> e[i].second;
x = e[i].first;
y = e[i].second;
G[-x].push_back(y);
G[-y].push_back(x);
}
for(i = -n ; i <= n ; i++)
{
if(i && !viz[i])
df(i);
}
for(i = 1 ; i <= dr ; i++)
{
if(!val[st[i]] && !val[-st[i]])
{
val[st[i]] = 1;
}
}
ok = 1;
for(i = 1 ; i <= m ; i++)
{
if(!(val[e[i].first] || val[e[i].second]))
{
ok = 0;
}
}
if(ok == 0)
{
fout << "-1\n";
return 0;
}
for(i = 1 ; i <= n ; i++)
fout << val[i] << " ";
}