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#include <bits/stdc++.h>
using namespace std;
 
typedef long long ll;
#define pb push_back
#define mp make_pair
#define f first
#define s second
 
int main()
{
    ios_base::sync_with_stdio(false);
    cout.tie(0);
    cin.tie(0);
 
 
    int n, m;
    cin >> n >> m;
    vector<int> graph[n+5];
    for(int i = 0; i < m; i++){
        int a, b;
        cin >> a >> b;
        graph[a-1].pb(b-1);
        graph[b-1].pb(a-1);
    }
    vector<bool> visited(n, false);
    vector<int> col(n, -1);
    for(int i = 0; i < n; i++){
        if(col[i] != -1) continue;
        visited[i] = true;
        col[i] = 1;
        queue<int> q;
        q.push(i);
        while(!q.empty()){
            int c = q.front(); q.pop();
            for(int j = 0; j < (int) graph[c].size(); j++){
                int z = graph[c][j];
                if(col[c] != -1 and col[z] != -1 and col[c] == col[z]) {
                    cout << "IMPOSSIBLE" << endl;
                    return 0;

}
                if(visited[z]) continue;
                visited[z] = true;
                if(col[z] == -1){
                    if(col[c] == 1) col[z] = 2;
                    if(col[c] == 2) col[z] = 1;
                    q.push(z);
                }else {
                    if(col[c] == col[z]){
                        cout << "IMPOSSIBLE" << endl;
                        return 0;
                    }
                }
            }
        }
    }
    
    for(int i = 0; i < n; i++){
        cout << col[i] << " ";
    }
    
    
    return 0;
 
}