explanation doubt cn

Question

http://ledr.luon.net/documents/2IC10/bas_mark/week1.pdf

in the exercise 9 of the pdf ...how did they calculated path length i+j-2 ...and moreover it if possible please derive it in easy way with explanation.....

Comments

they mention that i means a node in level i and j means a node in level j and root node is at level 1

every time i wants to communicate j ===> i to root and root to j

distance between i to root ---> maximum edges btw them ===> i-1 

distance between root to j ===> j-1 

i wants to communicate j ==> (i-1)+(j-1) = i+j-2

Answer 1

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