Enter the binary tree ... 1 / \ 2 3 / \ 4 5 \ / \ 8 6 7 / 9
struct Node * root = newNode ( 1 ) ; root -> left = newNode ( 2 ) ; root -> right = newNode ( 3 ) ; root -> left -> left = newNode ( 4 ) ; root -> left -> right = newNode ( 5 ) ; root -> left -> right -> left = newNode ( 6 ) ; root -> left -> right -> right = newNode ( 7 ) ; root -> left -> left -> right = newNode ( 8 ) ; root -> left -> left -> right -> left = newNode ( 9 ) ; diameter ( root ) ; return 0 ; }