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#include <cstdio>
#include <algorithm>
#include <vector>
#include <cstring>
using namespace std;
const int MAX_N=100100;
int n;
int per(int nod) {
if(nod>n) {
return nod-n;
}
return nod+n;
}
vector<int> A[2*MAX_N];
vector<int> B[2*MAX_N];
int st[2*MAX_N];
bool viz[2*MAX_N];
bool val[2*MAX_N];
void dfs1(int nod) {
viz[nod]=true;
for(vector<int>::iterator it=A[nod].begin(); it!=A[nod].end(); it++) {
if(!viz[*it]) {
dfs1(*it);
}
}
st[++st[0]]=nod;
//printf("%d ",nod>n?-(nod-n):nod);
}
bool no_sol=false;
void dfs2(int nod) {
//printf("%d ",nod>n?-(nod-n):nod);
if(val[nod]) {
no_sol=true;
}
viz[nod]=true;
val[per(nod)]=true;
for(vector<int>::iterator it=B[nod].begin(); it!=B[nod].end(); it++) {
if(!viz[*it]) {
dfs2(*it);
}
}
}
int main() {
freopen("2sat.in","r",stdin);
freopen("2sat.out","w",stdout);
int m;
scanf("%d%d",&n,&m);
for(int i=1;i<=m;i++) {
int a,b;
scanf("%d%d",&a,&b);
if(a<0) {
a=n-a;
}
if(b<0) {
b=n-b;
}
A[per(a)].push_back(b);
A[per(b)].push_back(a);
B[b].push_back(per(a));
B[a].push_back(per(b));
}
for(int i=1;i<=2*n;i++) {
if(!viz[i]) {
dfs1(i);
}
}
memset(viz,0,sizeof(viz));
for(int i=2*n;i>=1;i--) {
if(!viz[st[i]]&&!viz[per(st[i])]) {
dfs2(st[i]);
}
}
if(no_sol) {
printf("-1");
return 0;
}
for(int i=1;i<=n;i++) {
printf("%d ",val[i]);
}
return 0;
}