Function Symm

InterviewBit_problems/CP_BinaryTree/Solution.cpp:15–22

 int Symm(TreeNode* A,TreeNode* B)
 {
     if(A==NULL &&  B==NULL) return true; //tree is symmetric;only root node  left(such a case)
     if(A==NULL || B==NULL) return false;//after the above is checked ;see if node has only one child: then tree cannot be symmetric.
     //use following for the rest cases.
     return (A->val==B->val) && (Symm(A->left,B->right)) && (Symm(A->right,B->left));
      
 }

int Solution::isSymmetric(TreeNode* root) 
{