What is the Difference Between Tree and Graph in Data Structure?

The main difference between a tree and a graph in data structures lies in their connections and loop formation. Here are the key differences between the two:

1. Structure: A graph is a set of vertices (nodes) and edges, with no unique node known as the root. In contrast, a tree is a set of nodes and edges with a unique node called the root.
2. Loops: Graphs can form cycles or loops, while trees cannot.
3. Connections: In a graph, nodes can have any number of connections to other nodes. In a tree, each node can have at most one parent, except for the root node, which has no parent.
4. Hierarchy: A tree represents a hierarchical structure, where data is organized in multiple levels. A graph, on the other hand, can represent a network model with connections between vertices, allowing for loops.
5. Traversal Techniques: Graphs have two traversal techniques: breadth-first search and depth-first search. Trees have three traversal techniques: pre-order, in-order, and post-order.

In summary, a tree is a hierarchical and nonlinear data structure, while a graph is a more general nonlinear data structure that can have loops and cycles. Trees are typically used to represent data with a hierarchical structure, such as file systems, organization charts, and family trees, while graphs are used to represent networks, transportation networks, and computer networks.

Comparative Table: Tree vs Graph in Data Structure

Here is a table comparing the differences between trees and graphs in data structures:

Both trees and graphs are types of non-linear data structures, but they differ in terms of their connections and loop formation. Trees are used to represent hierarchical structures, while graphs can have loops and represent more complex networks, such as transportation networks and computer networks.