Challenge: Check if an Undirected Graph is Tree or not

Problem Statement #

The next section will tackle the tree data structure. For now, here’s the basic difference between a graph and a tree. A graph can only be a tree under two conditions:

• There are no cycles.
• The graph is connected.

A graph is connected when there is a path between every pair of vertices. In a connected graph, there are no unreachable vertices. Each vertex must be able to reach every other vertex through either a direct edge or through a graph traversal.

You have to implement isTree() function which will take a graph as input and find out if it is a tree.

Input #

An undirected graph.

Output #

Returns True if the given graph is a tree. Otherwise, it returns False.

Sample Input #

graph = {
    0 - 1
    0 - 2
    0 - 3
    3 - 4  
}

Sample Output #

true