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#include <bits/stdc++.h>
using namespace std;
ifstream cin("2sat.in");
ofstream cout("2sat.out");
vector <int> g[200001], gi[200001];
vector <int> ctc[200001];
int l[200001], k, ok[200001], t;
bool rez[200001], ok2[200001];
void arc(int x, int y, int n, vector <int> g[])
{
if (x < 0)
x = -x + n;
if (y < 0)
y = -y + n;
g[x].push_back(y);
}
void dfs1(int nod)
{
ok[nod] = -1;
for (auto x : gi[nod])
{
if (ok[x] == 0)
dfs1(x);
}
l[++t] = nod;
}
void dfs2(int nod)
{
ok[nod] = k;
ctc[k].push_back(nod);
for (auto x : g[nod])
{
if (ok[x] == -1)
dfs2(x);
}
}
bool check(int n)
{
for (int i = 1;i <= n;i++)
{
if (ok[i] == ok[i + n])
{
cout << -1;
return 0;
}
if (ok[i] <
ok[i + n])
rez[i] = 1;
}
return 1;
}
int main() {
int n, m, i, x, y;
cin >> n >> m;
for (i = 1;i <= m;i++)
{
cin >> x >> y;
arc(-x, y, n, g);
arc(-y, x, n, g);
arc(y, -x, n, gi);
arc(x, -y, n, gi);
}
for (i = 1;i <= n * 2;i++)
{
if (ok[i] == 0)
dfs1(i);
}
for (i = n * 2;i >= 1;i--)
{
if (ok[l[i]] == -1)
{
k++;
dfs2(l[i]);
}
}
if (check(n))
{
for (i = 1;i <= n;i++)
cout << rez[i] << " ";
}
return 0;
}