building teams

#include<bits/stdc++.h>
using namespace std;

int n, m;
vector<vector<int>> adj;
vector<int> vis;
bool isBipartite = true;

void dfs(int node, int color)
{
	vis[node] = color;

	for(auto it: adj[node])
	{
		if(vis[it] == 0)
		{
			dfs(it, 3 - color);
		}
		if(vis[it] == vis[node])
		{
			isBipartite = false;
			return;
		}
	}
}

int main()
{
	cin >> n >> m;

	adj = vector<vector<int>>(n+1);
	vis = vector<int>(n+1, 0);

	for(int i = 0; i < m; i++)
	{
		int u, v;
		cin >> u >> v;

		adj[u].push_back(v);
		adj[v].push_back(u);
	}

	for(int i = 1; i <= n; i++)
	{
		if(vis[i] == 0)
		{
			dfs(i, 1);
			if(!isBipartite) break;
		}
	}

	if(!isBipartite)
	{
		cout << "IMPOSSIBLE" << '\n';
	}
	else
	{
		for(int i = 1; i <= n; i++)
		{
			cout << vis[i] << " ";
		}
		cout << '\n';
	}


	return 0;
}