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#include<fstream>
#include<vector>
#include<stack>
#define DIM 100005
using namespace std;
int n, m, x, y, i, j, nr, cnt;
int f[DIM], viz[DIM], ctc[DIM], niv[DIM], low[DIM], sol[DIM], ff[DIM];
vector<int> v[DIM], w[DIM];
stack<int> s;
ifstream fin("2sat.in");
ofstream fout("2sat.out");
int inv(int x){
if(x <= n){
return x + n;
}
return x - n;
}
void dfs(int nod){
viz[nod] = f[nod] = 1;
s.push(nod);
cnt++;
low[nod] = niv[nod] = cnt;
for(int i = 0; i < v[nod].size(); i++){
int vecin = v[nod][i];
if(viz[vecin] == 0){
dfs(vecin);
}
if(f[vecin] == 1){
low[nod] = min(low[nod], low[vecin]);
}
}
if(low[nod] == niv[nod]){
nr++;
int x;
do{
x = s.top();
ctc[x] = nr;
f[x] = 0;
w[nr].push_back(x);
s.pop();
}while(x != nod);
}
}
int main(){
fin>> n >> m;
for(i = 1; i <= m; i++){
fin>> x >> y;
if(x < 0){
x = n - x;
}
if(y < 0){
y = n - y;
}
v[ inv(x) ].push_back(y);
v[ inv(y)].push_back(x);
}
for(i = 1; i <= 2 * n; i++){
if(viz[i] == 0){
dfs(i);
}
}
for(i = 1; i <= nr; i++){
if(ff[i] == 1){
continue;
}
for(j = 0; j < w[i].size(); j++){
x = w[i][j];
if(ctc[x] == ctc[ inv(x) ] ){
fout<<"-1\n";
return 0;
}
sol[x] = 1;
sol[ inv(x) ] = 0;
}
}
for(i = 1; i <= n; i++){
fout<< sol[i] <<" ";
}
return 0;
}