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#include <fstream>
#include <algorithm>
#include <vector>
#include <queue>
#include <cmath>
using namespace std;
ifstream cin ("2sat.in");
ofstream cout ("2sat.out");
int n, m, x, y;
bool viz[200005];
int val[100005], ind[200005], deg[200005];
vector <int> g[200005], ginv[200005];
vector <int> comp, st;
vector <vector <int>> comps;
queue <int> q;
int indx(int val) {
if(val < 0)
return n - val;
return val;
}
int non(int val) {
if(val > n)
return val - n;
return val + n;
}
void dfsp(int nod) {
viz[nod] = 1;
for(auto &fiu : g[nod]) {
if(!viz[fiu])
dfsp(fiu);
}
st.push_back(nod);
}
void dfsm(int nod) {
viz[nod] = 1;
comp.push_back(nod);
for(auto &fiu : ginv[nod]) {
if(!viz[fiu])
dfsm(fiu);
}
}
int main() {
cin >> n >> m;
for(int i = 1; i <= m; i++) {
cin >> x >> y;
g[non(indx(x))].push_back(indx(y));
g[non(indx(y))].push_back(indx(x));
ginv[indx(x)].push_back(non(indx(y)));
ginv[indx(y)].push_back(non(indx(x)));
}
for(int i = 1; i <= 2 * n; i++) {
if(!viz[i])
dfsp(i);
}
for(int i = 1; i <= 2 * n; i++)
viz[i] = 0;
while(!st.empty()) {
int nod = st.back();
st.pop_back();
if(!viz[nod]) {
comp.clear();
dfsm(nod);
for(auto &Nod : comp)
ind[Nod] = comps.size();
comps.push_back(comp);
}
}
for(int i = 1; i <= n; i++) {
cout << ind[i] << " " << ind[i + n] << "\n";
if(ind[i] == ind[i + n]) {
// nu are cum sa fie in ac comp cu negatia
cout << -1;
return 0;
}
}
for(int i = 1; i <= 2 * n; i++) {
for(auto &fiu : g[i]) {
if(ind[fiu] != ind[i])
deg[ind[fiu]]++;
}
}
for(int i = 1; i <= n; i++)
val[i] = 2;
for(int i = 0; i < comps.size(); i++) {
if(!deg[i])
q.push(i);
}
while(!q.empty()) {
int cmp = q.front();
q.pop();
for(auto &nod : comps[cmp]) {
int trueNod = (nod > n ? nod - n : nod);
if(val[trueNod] == 2)
val[trueNod] = (nod > n);
}
for(auto &nod : comps[cmp]) {
for(auto &fiu : g[nod]) {
if(ind[nod] != ind[fiu]) {
deg[ind[fiu]]--;
if(!deg[ind[fiu]])
q.push(ind[fiu]);
}
}
}
}
for(int i = 1; i <= n; i++)
cout << val[i] << " ";
return 0;
}