Hi,

I am a little bit stuck in understanding this question ....

Can someone please help me with this and explain how I find the answer?

"In a directed graph every vertex has an "in-degree" and an "out-degree".

The "in-degree" is the number of heads of edges (arrows) adjacent to a vertex, and the "out-degree" is the number of tails of edges adjacent to a vertex.

A tree is called a "rooted tree" if one vertex has been designated the root, which by definition must have an in-degree of 0 and an out-degree of 1.

All the other vertices must have an in-degree of 1.

Below is given an undirected tree. How many non-isomorphic "rooted trees" can be created from this tree by choosing an appropriate root?"

I would say you can create "10" trees here ... because there are 10 points where you can create a root of.

I just don't get the "non-isomorphic "rooted trees" part here ... kind of confuses me ...

Or is the answer "5" because I can only pick the vertices that are on "on the "left sides" and the vertices that are starting from below?

Or is the answer "1" because there is no way you can redraw this tree in another way?

Or is the answer 106 ... that we need to try to create a tree and see how many combinations is possible with 10 vertices?

I am kind of confused here ...

Thanks,