Let \(G=(V, E)\) be a graph. Define \(\xi(G) = \sum\limits_d i_d*d\) , where…

Let $G=(V, E)$ be a graph. Define $\xi(G) = \sum\limits_d i_d*d$ , where $i_d$ is the number of vertices of degree $d$ in $G$. If $S$ and $T$ are two different trees with $\xi(S) = \xi(T)$ , then