Symmetric Tree (Mirror Image of itself)

PROBLEM :

Given a binary tree, check whether it is a mirror of itself.

For example, this binary tree is symmetric:

     1
   /   \
  2     2
 / \   / \
3   4 4   3

But the following is not:

    1
   / \
  2   2
   \   \
   3    3
     
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SIMPLE c++ IMPLEMENTATION :
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/*
typedef struct BST
{
int info ;
struct BST *left ;
struct BST *right ;
}tree ;---------------------------------------------*/

// same root is send as argument twice
// Symmetric_Tree(root,root) ;

int Symmetric_Tree(tree *root1,tree *root2)
{
if(root1==NULL&&root2==NULL)
return 1 ;

if(root1->info==root2->info)
return (Symmetric_Tree(root1->left,root2->right)&&Symmetric_Tree(root1->right,root2->left)) ;

return 0 ;
}

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