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#include <fstream>
#include <vector>
#include <algorithm>
#include <bitset>
using namespace std;
string file = "2sat";
ifstream cin(file + ".in");
ofstream cout(file + ".out");
const int N = 100000;
vector <int> succesori[2 * N + 1], predecesori[2 * N + 1], ordine, ctc(2*N+1);
bitset <2 * N + 1> viz;
int nctc;
int val_asoc(int x)
{
return (x < 0 ? -2 * x - 1 : 2 * x);
}
int negatie(int x)
{
return (x % 2 ? x + 1 : x - 1);
}
void dfs_init(int x)
{
ordine.push_back(x);
viz[x] = 1;
for (int y : succesori[x])
{
if (!viz[y])
dfs_init(y);
}
}
void dfs_transpus(int x)
{
ctc[x] = nctc;
for (int y : predecesori[x])
{
if (ctc[y] == 0)
{
dfs_transpus(y);
}
}
}
int main()
{
int n, m, x, y;
cin >> n >> m;
for (int i = 0; i < m; i++)
{
cin >> x >> y;
x = val_asoc(x);
y = val_asoc(y);
succesori[negatie(x)].push_back(y);
predecesori[y].push_back(negatie(x));
succesori[negatie(y)].push_back(x);
predecesori[x].push_back(negatie(y));
}
for (int i = 1; i <= 2 * n; i++)
{
if (!viz[i])
{
dfs_init(i);
}
}
reverse(ordine.begin(), ordine.end());
for (int x : ordine)
{
if (ctc[x] == 0)
{
++nctc;
dfs_transpus(x);
}
}
bool este_sat(1);
for (int i = 1; i <= 2 * n; i+=2)
{
if (ctc[i] == ctc[i+1])
{
este_sat = 0;
break;
}
}
if (!este_sat)
{
cout << -1;
}
else
{
for (int i = 1; i < 2*n; i+=2)
{
cout << (ctc[i] < ctc[i + 1]) << ' ';
}
}
}