The Difference Between a Tree and a Graph Data Structure
Learn the difference between a tree and a graph data structure.
Jennifer Bland
In JavaScript programming, data can be stored in data structures like graphs and trees. Technically trees are graphs.
Graphs Data Structures
A graph consists of a set of nodes and a set of edges. An edge is a pair of nodes that are connected. A path is the term used to describe traveling between nodes that share an edge. The image below shows a graph with 3 nods and 3 edges.
Tree Data Structure
This repeats until all data is represented in the tree data structure. The image below shows a tree data structure.
A tree is a graph that has no cycles (a cycle being a path in the graph that starts and ends at the same vertex). A child node can only have one parent. For this reason trees are not a recursive data structure.
Why Use Graphs and Trees as Data Structures?
The most common implementations of a graph are finding a path between two nodes, finding the shortest path from one node to another and finding the shortest path that visits all nodes.
The traveling salesman problem is a great example of using a tree algorithm to solve a problem.
In my next post I will talk about the two methods to search a tree - breadth first search and depth first search.