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Title: “Program Assignment 3: Graph Shortest Path Problems”
Points: 100 points – 60pts for coded portion, 40 points for written analysis
Due Date: Monday December 2, 2002 (last day of class)
Objectives: (1) To implement graph data structures in Java. (2) To implement two classical graph
shortest path algorithms.
Description: Create a Java program that will produce the shortest path through (1) a positively
weighted directed graph using Dijkstra’s algorithm and (2) a directed graph with negative weights
using Ford’s algorithm. Note: Ford’s algorithm works for either positive or negative edge weights,
for our purposes here, use only Dijkstra for positively weighted graphs and use Ford exclusively for
negatively weighted graphs. Do this according to the steps shown below:
1. You will need to implement a graph data structure capable of storing the weights of the
edges in the graph. See Day 22 notes for graph implementation techniques, your choice of
which technique to use.
2. For each graph containing only positive weights, run Dijkstra’s algorithm on the graph and
produce the shortest path through the graph, given start and destination vertices. Your
program should print the vertices in the path as well as the length of this path.
3. For each graph that contains a negatively weighted edge, run Ford’s algorithm on the graph
and produce the shortest path through the graph, given start and destination vertices. Your
program should print the vertices in the path as well as the length of this path.
References:
Notes: Lecture Notes for Days 22 & 23
Restrictions:
Your source file shall begin with comments containing the following information:
/* Name:
COP 3503H
Assignment title:
Date:
*/
Input Specification: I will place on the website a set of graphs that will be used as input for your
program. Use any graph you want for testing purposes, but the runs you
submit for grading must use the graphs on the website. Rather than require
everyone to use the same rigid input format, I will leave it up to you as to
how to input the graph information. I will supply it to you in the following
format: (emanating vertex, incident vertex, weight). As an example, the
following set of data would produce the graph shown below:
(A, B, 4) (C, D, -3) (B, D, 5) (D, E, 2) (C, A, 3) (E, B, 2) (D, A, 4)
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COP 3503H – Programming Assignment #3 – Fall 2002
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