3.18 二叉树的镜像

操作给定的二叉树，将其变换为源二叉树的镜像。

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) {
		if (NULL == pRoot) {
			return;
		}

		if (NULL == pRoot->left && NULL == pRoot->right) {
			return;
		}

		TreeNode* temp = pRoot->left;
		pRoot->left = pRoot->right;
		pRoot->right = temp;

		Mirror(pRoot->left);
		Mirror(pRoot->right);
	}
};

测试