Question

Write a c++ function that will

a. determine whether two binary trees are mirror similar.

b. determine whether two binary trees are isomorphic.

c. replace a given value in a binary search tree with a new value keeping the tree as a binary search tree.

d. create a new tree composed of words in another tree in reverse order

e. create a 0-2 binary search tree based on existing non 0-2 binary search tree

Answer 1

a)

CODE

/* Given two trees, return true if they are

   mirror of each other */

int areMirror(Node* a, Node* b)

{

    /* Base case : Both empty */

    if (a==NULL && b==NULL)

        return true;

  

    // If only one is empty

    if (a==NULL || b == NULL)

        return false;

  

    /* Both non-empty, compare them recursively

     Note that in recursive calls, we pass left

     of one tree and right of other tree */

    return a->data == b->data &&

            areMirror(a->left, b->right) &&

            areMirror(a->right, b->left);

}

b)

CODE

/* Given a binary tree, print its nodes in reverse level order */

bool isIsomorphic(node* n1, node *n2)

{

// Both roots are NULL, trees isomorphic by definition

if (n1 == NULL && n2 == NULL)

    return true;

  

// Exactly one of the n1 and n2 is NULL, trees not isomorphic

if (n1 == NULL || n2 == NULL)

    return false;

  

if (n1->data != n2->data)

    return false;

  

// There are two possible cases for n1 and n2 to be isomorphic

// Case 1: The subtrees rooted at these nodes have NOT been "Flipped".

// Both of these subtrees have to be isomorphic, hence the &&

// Case 2: The subtrees rooted at these nodes have been "Flipped"

return

(isIsomorphic(n1->left,n2->left) && isIsomorphic(n1->right,n2->right))||

(isIsomorphic(n1->left,n2->right) && isIsomorphic(n1->right,n2->left));

}

  

NOTE: As per Chegg policy, I am allowed to answer only 2 coding questions (including sub-parts) on a single post. Kindly post the remaining questions separately and I will try to answer them. Sorry for the inconvenience caused.