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!

```
package org.gs.graph
/** Undirected graph
*
* @constructor creates a new Graph with vertex count
* @param v number of vertices
* @see [[https://algs4.cs.princeton.edu/41undirected/Graph.java.html]]
* @author Scala translation by Gary Struthers from Java by Robert Sedgewick and Kevin Wayne.
*/
class Graph(v: Int) extends BaseGraph(v) {
/** add edge between vertices v and other then add v to other's adjacency list */
override def addEdge(v: Int, other: Int): Unit = {
super.addEdge(v, other)
adj(other) = v :: adj(other)
}
}
```