Difference between graph and tree:
• A tree can be described as a specialized case of graph with no self loops and circuits.
• There are no loops in a tree whereas a graph can have loops.
• There are three sets in a graph i.e. edges, vertices and a set that represents their relation while a tree consists of nodes that are connected to each other. These connections are referred to as edges.
• In tree there are numerous rules spelling out how connections of nodes can occur whereas graph has no rules dictating the connection among the nodes.

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