Book Image

Beginning Java Data Structures and Algorithms

By : James Cutajar
Book Image

Beginning Java Data Structures and Algorithms

By: James Cutajar

Overview of this book

Learning about data structures and algorithms gives you a better insight on how to solve common programming problems. Most of the problems faced everyday by programmers have been solved, tried, and tested. By knowing how these solutions work, you can ensure that you choose the right tool when you face these problems. This book teaches you tools that you can use to build efficient applications. It starts with an introduction to algorithms and big O notation, later explains bubble, merge, quicksort, and other popular programming patterns. You’ll also learn about data structures such as binary trees, hash tables, and graphs. The book progresses to advanced concepts, such as algorithm design paradigms and graph theory. By the end of the book, you will know how to correctly implement common algorithms and data structures within your applications.
Table of Contents (8 chapters)

Calculating Shortest Paths


The shortest path is a path between two vertices so that the sum of the weights of the edges that constitute the path is minimized. The shortest path problem has many applications in the real world, from finding directions on mapping applications to minimizing the moves to solve a puzzle.

In this section, we shall look at two different strategies for computing shortest paths: one that finds the shortest paths from a single source to every other vertex in the graph, and another that finds shortest paths between all pairs of vertices in a graph.

Single Source Shortest Path: Dijkstra's Algorithm

When we explored BFS, we saw that it was able to solve the shortest path problem for unweighted graphs, or graphs whose edges have the same (positive) weight. What if we are dealing with weighted graphs? Can we do better? We shall see that Dijkstra's algorithm provides an improvement over the ideas presented in BFS and that it is an efficient algorithm for solving the single...