Modified Depth First Search Implementation in Ruby/Python - CLRS prob 22-2, pg 621

Purpose: This project implements a modified depth first search algorithm of a connected undirected graph. Convert my pseudocode to find the articulation points and biconnected components of a graph into a working program. An articulation point of G is a vertex whose removal disconnects G. A biconnected component of G is a maximal set of edges such that any two edges in the set lie on a common simple cycle.

Pseudocode: https://codeshare.io/29QD3V
My current implementation in Ruby: https://codeshare.io/5DbN33

Input: Given a txt file with nodes, parse the file. File is to represent the graphs with 72 nodes: https://codeshare.io/50p4lv
How to read the file: For example in a smaller test case with a Graph of 5 nodes:
5
2 4 5 -1
1 5 -1
5 -1
1 5 -1
1 2 3 4 -1
The graph would look like this: https://s17.postimg.cc/fs0uvl83j/IMG-3386.jpg

Output: List of articulation points of the graph. List of bi connected components.
Required classes: class Node, class Graph, class MainApp to initialize DFS_Visit functions.
Language: Ruby

This problem is related to 22-2 Articulation points, bridges, and bi-connected components in CLRS textbook (see attachment).