Retrieve the NodeData sibling of a given object in the tree $($via pass$-$by$-$reference, second parameter which may

initially be garbage$).$ It will be a copy of the actual object in the tree $($if param $1$ exists and is found$).$

SPECIAL INSTRUCTIONS: For this function, you do not get to know that the tree is a binary search tree.

You must solve the problem for a general binary tree where data could be stored anywhere $($e$.$g$.,$ tree T$4$ above$).$

bool getSibling$($const NodeData&$,$ NodeData&$)$ const;

$--$ Retrieve the NodeData parent of a given object in the tree $($via pass$-$by$-$reference, second parameter which may

initially be garbage$).$ It will be a copy of the actual object in the tree $($if param $1$ exists and is found$).$

SPECIAL INSTRUCTIONS: Ditto getSibling$(),$ you do not get to know that the tree is a binary search tree.

bool getParent$($const NodeData&$,$ NodeData&$)$ const;