In this problem, you need to complete a function `Node* getTreeMirror(Node*)`

. This function accepts the root of a binary tree as its parameter. It should modify the tree, such that the resultant tree is the mirror image of the original tree. The mirror image of a binary tree is defined as another tree whose left and right children of all non-leaf nodes are interchanged.

If you give the correct mirror images of all trees you will receive a YES from us, else you will receive a NO.