Definitely. In a (directed) tree there are exactly 0 or 1 paths between two nodes. There's no such thing as a shortest path. In an undirected tree there's exact

Definitely. In a (directed) tree there are exactly 0 or 1 paths between two nodes. There's no such thing as a shortest path. In an undirected tree there's exactly 1 path between any two nodes---even worse. You might be representing a graph with a tree however if your nodes are labeled and you want to talk about the shortest path between two nodes quotiented by those labels.