IsoMorphic Binary Trees

Two trees can be called isomorphic if they have similar structure and the only difference amongst them can be is, that their child nodes may or may not be swapped..

For example

The trees in the above picture are called  Isomorphic Trees.The following code checks whether two trees are Isomorphic or not.

Code:(Written in C)

int is_isomorphic(struct node *t1,struct node *t2)
{
if(t1==NULL && t2==NULL)
            return 1;
if(t1==NULL || t2==NULL || t1->data!=t2->data)
return 0;
return  (is_isomorphic(t1->left,t2->left)&&is_isomorphic(t1->right,t2->right) || is_isomorphic(t1->left,t2->right)&&is_isomorphic(t1->right,t2->left) );
}

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