T5 一般树结点与度的关系

$$\{\begin{array}{l}n={\sum }_{i=0}^k{n}_i\\ n={\sum }_{i=1}^{k}i\cdot n_i+1\end{array}\Rightarrow n_0=1+\sum _{i=1}^k(i-1)\cdot n_i$$