<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:
vector<int> nearFinder(int n, const vector<vector<int>>& dislikes) {
    vector<int> toR;
    for (const auto& dislike : dislikes) {
        if (dislike[0] == n) {
            toR.push_back(dislike[1]);
        } else if (dislike[1] == n) {
            toR.push_back(dislike[0]);
        }
    }
    return toR;
}

bool possibleBipartition(int n, const vector<vector<int>>& dislikes) {
    vector<int> visited(n + 1, -1);
    queue<int> toVisit;

    for (int i = 1; i <= n; i++) {
        if (visited[i] == -1) { 
            visited[i] = 0;
            toVisit.push(i);

            while (!toVisit.empty()) {
                int f = toVisit.front();
                toVisit.pop();

                vector<int> neighbors = nearFinder(f, dislikes);
                for (int neighbor : neighbors) {
                    if (visited[neighbor] == -1) {
                        visited[neighbor] = !visited[f];
                        toVisit.push(neighbor);
                    } else if (visited[neighbor] == visited[f]) {
                        return false;
                    }
                }
            }
        }
    }

    return true;
}
};
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