Check if Tree is Isomorphic

Problem Statement

Pattern:

---

Solution

boolean isIsomorphic(Node root1, Node root2)  
{ 
	// code here.
	if(root1 == null && root2 == null) return true;
	if(root1 == null || root2 == null) return false;
	
	if(root1.data != root2.data) return false;
	
	return (isIsomorphic(root1.left,root2.left) && isIsomorphic(root1.right,root2.right)) ||
   (isIsomorphic(root1.left,root2.right) && isIsomorphic(root1.right,root2.left));
}

Notes

• either corresponding left and right nodes of a node have to be the same
• or opposite corresponding left and right nodes of a node have to be the same