Write C code to determine if two trees are identical

Here is a C program using recursion

int identical(struct node* a, struct node* b)
{
if (a==NULL && b==NULL){return(true);}
else if (a!=NULL && b!=NULL)
{
return(a->data == b->data &&
identical(a->left, b->left) &&
identical(a->right, b->right));
}
else return(false);
}