Or, if the structure is this: struct node { struct node *left_node; struct node *right_node; int val; }; struc

Or, if the structure is this: struct node { struct node *left_node; struct node *right_node; int val; }; struct reversed_node { struct reversed_node *right_node; struct reversed_node *left_node; int val; }; No? You then just have a different mapping for the exact same data, no traversal needed.