操作给定的二叉树，将其变换为源二叉树的镜像。

二叉树的镜像定义：源二叉树

    	    8

    	   /  \

    	  6   10

    	 / \  / \

    	5  7 9 11

    	镜像二叉树

    	    8

    	   /  \

    	  10   6

    	 / \  / \

    	11 9 7  5

/*

struct TreeNode {

	int val;

	struct TreeNode *left;

	struct TreeNode *right;

	TreeNode(int x) :

			val(x), left(NULL), right(NULL) {

	}

};*/

class Solution {

public:

    void Mirror(TreeNode *pRoot) {

        TreeNode* tmp;

        if(pRoot == NULL){

            return;

        }

        tmp = pRoot->right;

        pRoot->right = pRoot->left;

        pRoot->left = tmp;

        Mirror(pRoot->right);

        Mirror(pRoot->left);

    }

};