Question 1

What is the fundamental difference between a Tree and a Graph?

Accepted Answer

A Tree is a restricted form of a Graph. The main differences are that a Tree is always acyclic (contains no cycles) and is always connected. A Graph, on the other hand, can have cycles and may not be connected (it can consist of several disjoint subgraphs). Also, in a tree, there is a unique path between any two nodes, which is not necessarily true for a graph.

Question 2

Can a Tree be considered a Graph?

Accepted Answer

Yes, a Tree is a special type of Graph. Specifically, it is an undirected, connected, acyclic graph. All trees are graphs, but not all graphs are trees.

Graph vs. Tree Interview Questions

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