In graph theory, a regular graph is a graph where each vertex has the same number of neighbors; i.e. every vertex has the same degree or valency. Also, from the handshaking lemma, a regular graph of odd degree will contain an even number of vertices.

COMING SOON!

```
/*
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package com.algorithmexamples.graphs
interface Graph {
public val V: Int
public var E: Int
public fun adjacentVertices(from: Int): Collection<Int>
public fun vertices(): IntRange = 0 until V
}
```