sword to offer 018

struct TreeNode {
	int val;
	struct TreeNode *left;
	struct TreeNode *right;
	TreeNode(int x) :
			val(x), left(NULL), right(NULL) {
	}
};*/
class  {
private:
    void Modify(TreeNode* pRoot) {
        if(!pRoot) {
            return ;
        }
        TreeNode* tempNode = pRoot->left;
        pRoot->left = pRoot->right;
        pRoot->right = tempNode;
        Modify(pRoot->left);
        Modify(pRoot->right);
    }
public:
    void Mirror(TreeNode *pRoot) {
        Modify(pRoot);
    }
};