剑指Offer-19-二叉树的镜像

原二叉树
8
1       2
3       4
则输出
8
2       1
4       3

#include <iostream>
using namespace std;

struct BinaryTreeNode {
int m_nValue;
struct BinaryTreeNode *m_pLeft;
struct BinaryTreeNode *m_pRight;
};

void MirrorRecursively(BinaryTreeNode *pNode) {
if(pNode == NULL)
return;
if(pNode->m_pLeft==NULL && pNode->m_pRight==NULL)
return;
BinaryTreeNode *t = pNode->m_pLeft;
pNode->m_pLeft = pNode->m_pRight;
pNode->m_pRight = t;
MirrorRecursively(pNode->m_pLeft);
MirrorRecursively(pNode->m_pRight);
}