2023 SPRING CS 445 LAB #8:
WRITING THE GRAPH CLASS

Background:

AboutGraphs

The Graph class you will write uses uses a 2D array of int as the backing data structure.

Be sure to read document linked at very bottom of this page.

This assignment was borrowed and converted from C++ to Java as needed by Tim Hoffman with permission from it's original author Mark Stehlik

Here are the given files:

Graph.java // COMPLETE THE CODING INSIDE
graphdata.txt // PASS ON CMD LINE AS ARGS[0]
TinyTester.java // USE THIS AS YOU DEVLEOP EACH METHOD
GraphTester.java // FULL TESTER I WILL USE ON YOUR GRAPH CLASS
Expected Output
How You Will Be Graded

Development Strategy

Finish the loadGraph() method. It is called from the constructor.
Finish the toString() method. It is called from the Tester
Run your Graph class against the TinyTester until everything works right.
Once you are sure the TinyTester produces correct output start running your Graph class against the real GraphTester.java and write/test one method at a time.
WRITE AND TEST METHODS -ONE AT A TIME-

The degree of a vertex is the number of edges incident to that vertex. For a directed graph, we can define the following terms:

outDegree - the number of edges leaving the vertex
inDegree - the number of edges entering the vertex
degree - the number of edges entering and leaving the vertex
You are to declare and implement private member functions for each of the above and private method
boolean hasEdge( int src, int dest) -- T/F whether there is an edge from src node to dest node

After doing so and testing your implementation, you are to implement the following 7 public methods in your Graph.java file to exercise the 4 private member functions above,

maxOutDegree - the maximal number of edges leaving any single vertex
minOutDegree - the minimal number of edges leaving any single vertex
maxInDegree - the maximal number of edges entering any single vertex
minInDegree - the minimal number of edges entering any single vertex
maxDegree - the maximal number of edges entering/leaving any single vertex
minDegree - the minimal number of edges entering/leaving any single vertex
removeEdge - puts a NO_EDGE value into the matrix or throws an Exception if bad values were passed in
For our input file, graphdata.txt, the correct answers are:

maxOutDegree - 3
minOutDegree - 1
maxInDegree - 4
minInDegree - 0
maxDegree - 5
minDegree - 2

This page explains each method and how to write it: Graph Class