<p>We want to split a group of <code>n</code> people (labeled from <code>1</code> to <code>n</code>) into two groups of <strong>any size</strong>. Each person may dislike some other people, and they should not go into the same group.</p>

<p>Given the integer <code>n</code> and the array <code>dislikes</code> where <code>dislikes[i] = [a<sub>i</sub>, b<sub>i</sub>]</code> indicates that the person labeled <code>a<sub>i</sub></code> does not like the person labeled <code>b<sub>i</sub></code>, return <code>true</code> <em>if it is possible to split everyone into two groups in this way</em>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> n = 4, dislikes = [[1,2],[1,3],[2,4]]
<strong>Output:</strong> true
<strong>Explanation:</strong> The first group has [1,4], and the second group has [2,3].
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> n = 3, dislikes = [[1,2],[1,3],[2,3]]
<strong>Output:</strong> false
<strong>Explanation:</strong> We need at least 3 groups to divide them. We cannot put them in two groups.
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= n &lt;= 2000</code></li>
	<li><code>0 &lt;= dislikes.length &lt;= 10<sup>4</sup></code></li>
	<li><code>dislikes[i].length == 2</code></li>
	<li><code>1 &lt;= a<sub>i</sub> &lt; b<sub>i</sub> &lt;= n</code></li>
	<li>All the pairs of <code>dislikes</code> are <strong>unique</strong>.</li>
</ul>

class Solution {
public:
bool possibleBipartition(int n, vector<vector<int>> dislikes) {
	vector<int> adj[n];
	for(auto i : dislikes){
		adj[i[0] -1].push_back(i[1] -1);
        adj[i[1] -1].push_back(i[0] -1);
	}
	vector<int> vis(n,0);
	vector<char> color(n,'n');
	queue<int> 	q;
	for(int i=0;i<n;i++){
		if(!vis[i] && adj[i].size()!=0){
			q.push(i);
			color[i]='g';
			vis[i]=1;
			while(!q.empty()){
				int node = q.front();
				q.pop();
				for(auto v:adj[node]){
					if(!vis[v]){
						color[v]= color[node]=='g'? 'b' : 'g';
						vis[v]=1;
						q.push(v);
					}
					else if(color[v]==color[node]) return false;
				}
			}
		}
	}
	
	return true;


}

};
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