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#include <iostream>
#include <fstream>
#include <vector>
#include <stack>
#define NMAX 2*100005
#define MMAX 200005
using namespace std;
int n, m;
vector<int> g[NMAX], gt[NMAX];
int comp[NMAX], res[NMAX];
vector<vector<int>> conex;
bool viz[NMAX] = { 0 };
stack<int> s, top;
void dfs1(int u) {
if (viz[u]) return;
viz[u] = true;
for (auto v : g[u])
dfs1(v);
s.push(u);
top.push(u);
}
void dfs2(int u, vector<int>& comp) {
if (viz[u]) return;
viz[u] = true;
comp.push_back(u);
for (auto v : gt[u])
dfs2(v, comp);
}
void build_gt() {
for (int i = 0;i < 2 * n;++i)
for (auto j : g[i]) {
gt[j].push_back(i);
}
}
bool is_sat() {
for (int i = 1;i <= n;++i)
if (comp[i + n] == comp[-i + n])
return false;
return true;
}
int abs(int x) {
return ((x < 0) ? -x : x);
}
int main() {
ifstream fin("2sat.in");
ofstream fout("2sat.out");
fin >> n >> m;
for (int i = 1;i <= m;++i) {
int x, y;
fin >> x >> y;
g[-x + n].push_back(y + n);
g[-y + n].push_back(x + n);
}
for (int i = 0;i < 2 * n;++i)
dfs1(i);
build_gt();
for (int i = 0;i < 2 * n;++i)
viz[i] = false;
while (!s.empty()) {
vector<int> v;
dfs2(s.top(), v);
s.pop();
for (auto x : v)
comp[x] = conex.size();
conex.push_back(v);
}
if (is_sat() == false) {
cout << -1;
return 0;
}
for (int i = 1;i <= n;++i)
res[i] = -1;
while (!top.empty()) {
int x = top.top();
top.pop();
x -= n;
if (res[abs(x)] != -1) continue;
if (x < 0)
res[-x] = 1;
else res[x] = 0;
}
for (int i = 1;i <= n;++i)
fout << res[i] << ' ';
return 0;
}