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#include<iostream>
#include<fstream>
#include<vector>
#include<cstring>
#include<map>
#include<algorithm>
#include<set>
#include<deque>
#include<queue>
using namespace std;
const int mx=4e5;
ifstream in("2sat.in");
ofstream out("2sat.out");
vector<int> g[mx],gt[mx],q;
bool visited[mx],possible=true;
int n,m,result[mx];
int node(int x){
if(x<0){
return n+abs(x);
}
return x;
}
int val(int node){
if(node>n){
return n-node;
}
return node;
}
void read(){
in>>n>>m;
int a,b;
for(int i=0;i<m;i++){
in>>a>>b;
g[node(-a)].push_back(node(b));
gt[node(b)].push_back(node(-a));
g[node(-b)].push_back(node(a));
gt[node(a)].push_back(node(-b));
}
}
void dfs1(int x){
visited[x]=true;
for(int k:g[x]){
if(!visited[k])
dfs1(k);
}
q.push_back(x);
}
void dfs2(int x,int value){
if(result[x]!=-1 && value!=result[x])
possible=false;
visited[x]=true;
result[x]=value;
result[node(-val(x))]=1-value;
for(int k:gt[x]){
if(!visited[k]){
dfs2(k,value);
}
}
}
void preprocess(){
for(int i=1;i<=2*n;i++)
result[i]=-1;
}
void solve(){
for(int i=1;i<=2*n;i++){
if(!visited[i]){
dfs1(i);
}
}
for(int i=1;i<mx;i++)
visited[i]=false;
bool possible=true;
for(auto iter=q.rbegin();iter!=q.rend();iter++){
if(!visited[*iter]){
dfs2(*iter,1);
}
}
if(!possible){
out<<-1;
return;
}
for(int i=1;i<=n;i++)
out<<result[i]<<" ";
}
int main(){
read();
solve();
return 0;
}