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#include <fstream>
#include <vector>
#include <cstdlib>
#include <stack>
using namespace std;
ifstream in("2sat.in");
ofstream out("2sat.out");
const int N = 1e5;
vector <int> aux[2*N+1], aux_t[2*N+1];
vector <int> *a, *a_t;
int n;
bool aux_viz[2*N+1] , aux_viz_t[2*N+1] , aux_val[2*N+1] , aux_completat[2*N+1] ;
bool *viz , *viz_t , *val , *completat;
stack <int> stiva;
void dfs( int x )
{
viz[x] = true;
for ( auto y : a[x] )
{
if ( !viz[y] )
{
dfs(y);
}
}
stiva.push(x);
}
void dfs_t( int x )
{
viz_t[x] = true;
if ( !completat[x] )
{
completat[x] = true;
val[x] = false;
completat[-x] = true;
val[-x] = true;
}
else
{
if ( val[x] )
{
out << -1;
out.close();
exit(0);
}
}
for ( auto y: a_t[x] )
{
if ( !viz_t[y] )
{
dfs_t(y);
}
}
}
int main()
{
int m;
in >> n >> m;
a = aux + N;
a_t = aux_t + N;
viz = aux_viz + N;
viz_t = aux_viz_t + N;
val = aux_val + N;
completat = aux_completat + N;
for ( int i = 0; i < m; i++ )
{
int x, y;
in >> x >> y;
a[-x].push_back(y);
a_t[y].push_back(-x);
a[-y].push_back(x);
a_t[x].push_back(-y);
}
in.close();
for ( int i = -n ; i <= n ; i++ )
{
if (!viz[i])
{
dfs(i);
}
}
while ( !stiva.empty() )
{
int x = stiva.top();
stiva.pop();
if ( completat[x] )
{
break;
}
if ( !viz_t[x] )
{
dfs_t(x);
}
}
for ( int i = 1 ; i <= n ; i++ )
{
out << val[i] << " ";
}
out.close();
return 0;
}