//大神解答
TreeNode *MirrorRecursively(TreeNode *pRoot){
if( pRoot == NULL )
return NULL;
TreeNode *temp = pRoot -> left;
pRoot -> left = MirrorRecursively(pRoot -> right);
pRoot -> right = MirrorRecursively(temp);
return pRoot;
}
//书上解答，写的更易懂
void MirrorRecursively(TreeNode *pRoot){
if(pRoot == NULL)
return;
if(pRoot -> left == NULL || pRoot -> right == NULL )
return;
TreeNode *temp = pRoot -> left;
pRoot -> left = pRoot -> right;
pRoot -> right = temp;
if(pRoot -> left)
MirrorRecursively(pRoot -> left);
if(pRoot -> right)
MirrorRecursively(pRoot -> right);
}
void MirrorRecursively(BinaryTreeNode *pNode)
{
if((pNode == NULL) || (pNode->m_pLeft == NULL && pNode->m_pRight))
return;
BinaryTreeNode *pTemp = pNode->m_pLeft;
pNode->m_pLeft = pNode->m_pRight;
pNode->m_pRight = pTemp;
if(pNode->m_pLeft)
MirrorRecursively(pNode->m_pLeft);
if(pNode->m_pRight)
MirrorRecursively(pNode->m_pRight);
}
// 测试二叉树：出叶子结点之外，左右的结点都有且只有一个左子结点
// 8
// 7
// 6
// 5
// 4
void Test2()
{
printf("=====Test2 starts:=====\n");
BinaryTreeNode* pNode8 = CreateBinaryTreeNode(8);
BinaryTreeNode* pNode7 = CreateBinaryTreeNode(7);
BinaryTreeNode* pNode6 = CreateBinaryTreeNode(6);
BinaryTreeNode* pNode5 = CreateBinaryTreeNode(5);
BinaryTreeNode* pNode4 = CreateBinaryTreeNode(4);
ConnectTreeNodes(pNode8, pNode7, NULL);
ConnectTreeNodes(pNode7, pNode6, NULL);
ConnectTreeNodes(pNode6, pNode5, NULL);
ConnectTreeNodes(pNode5, pNode4, NULL);
PrintTree(pNode8);
printf("=====Test2: MirrorRecursively=====\n");
MirrorRecursively(pNode8);
PrintTree(pNode8);
printf("=====Test2: MirrorIteratively=====\n");
MirrorIteratively(pNode8);
PrintTree(pNode8);
DestroyTree(pNode8);
}
// ====================测试代码====================
// 测试完全二叉树：除了叶子节点，其他节点都有两个子节点
// 8
// 6 10
// 5 7 9 11
void Test1()
{
printf("=====Test1 starts:=====\n");
BinaryTreeNode* pNode8 = CreateBinaryTreeNode(8);
BinaryTreeNode* pNode6 = CreateBinaryTreeNode(6);
BinaryTreeNode* pNode10 = CreateBinaryTreeNode(10);
BinaryTreeNode* pNode5 = CreateBinaryTreeNode(5);
BinaryTreeNode* pNode7 = CreateBinaryTreeNode(7);
BinaryTreeNode* pNode9 = CreateBinaryTreeNode(9);
BinaryTreeNode* pNode11 = CreateBinaryTreeNode(11);
ConnectTreeNodes(pNode8, pNode6, pNode10);
ConnectTreeNodes(pNode6, pNode5, pNode7);
ConnectTreeNodes(pNode10, pNode9, pNode11);
PrintTree(pNode8);
printf("=====Test1: MirrorRecursively=====\n");
MirrorRecursively(pNode8);
PrintTree(pNode8);
printf("=====Test1: MirrorIteratively=====\n");
MirrorIteratively(pNode8);
PrintTree(pNode8);
DestroyTree(pNode8);
}
// 测试只有一个结点的二叉树
void Test5()
{
printf("=====Test5 starts:=====\n");
BinaryTreeNode* pNode8 = CreateBinaryTreeNode(8);
PrintTree(pNode8);
printf("=====Test4: MirrorRecursively=====\n");
MirrorRecursively(pNode8);
PrintTree(pNode8);
printf("=====Test4: MirrorIteratively=====\n");
MirrorIteratively(pNode8);
PrintTree(pNode8);
}
// 测试空二叉树：根结点为空指针
void Test4()
{
printf("=====Test4 starts:=====\n");
BinaryTreeNode* pNode = NULL;
PrintTree(pNode);
printf("=====Test4: MirrorRecursively=====\n");
MirrorRecursively(pNode);
PrintTree(pNode);
printf("=====Test4: MirrorIteratively=====\n");
MirrorIteratively(pNode);
PrintTree(pNode);
}
