assert(TRUE == delete_node_from_tree(&pTreeNode, 10));
assert(5 == pTreeNode->data);
assert(NULL == pTreeNode->parent);
free(pTreeNode->left_child);
free(pTreeNode);
}
static void test4()
{
TREE_NODE* pTreeNode = NULL;
assert(TRUE == insert_node_into_tree(&pTreeNode, 10));
assert(TRUE == insert_node_into_tree(&pTreeNode, 5));
assert(TRUE == insert_node_into_tree(&pTreeNode, 3));
assert(TRUE == delete_node_from_tree(&pTreeNode, 10));
assert(5 == pTreeNode->data);
assert(NULL == pTreeNode->parent);
free(pTreeNode->left_child);
free(pTreeNode);
} 2.3 删除根数据时，没有左子树节点，只有右子树节点
/*
*
* 10 ======> 15
* / \ / \
* NULL 15 NULL 20
* \
* 20
*/
/*
*
* 10 ======> 15
* / \ / \
* NULL 15 NULL 20
* \
* 20
*/ 上面的代码表示了节点的删除过程。我们可以按照这个流程编写代码。
STATUS delete_node_from_tree(TREE_NODE** ppTreeNode, int data)
{
TREE_NODE* pTreeNode;
if(NULL == ppTreeNode || NULL == *ppTreeNode)
return FALSE;
pTreeNode = find_data_in_tree_node(*ppTreeNode, data);
if(NULL == pTreeNode)
return FALSE;
if(*ppTreeNode == pTreeNode){
if(NULL == pTreeNode->left_child && NULL == pTreeNode->right_child){
*ppTreeNode = NULL;
}else if(NULL != pTreeNode->left_child && NULL == pTreeNode->right_child){
*ppTreeNode = pTreeNode->left_child;
pTreeNode->left_child->parent = NULL;
}else if(NULL == pTreeNode->left_child && NULL != pTreeNode->right_child){
*ppTreeNode = pTreeNode->right_child;
pTreeNode->right_child->parent = NULL;
}
free(pTreeNode);
return TRUE;
}
return TRUE;
}
STATUS delete_node_from_tree(TREE_NODE** ppTreeNode, int data)
{
TREE_NODE* pTreeNode;
if(NULL == ppTreeNode || NULL == *ppTreeNode)
return FALSE;
pTreeNode = find_data_in_tree_node(*ppTreeNode, data);
if(NULL == pTreeNode)
return FALSE;
if(*ppTreeNode == pTreeNode){
if(NULL == pTreeNode->left_child && NULL == pTreeNode->right_child){
*ppTreeNode = NULL;
}else if(NULL != pTreeNode->left_child && NULL == pTreeNode->right_child){
*ppTreeNode = pTreeNode->left_child;
pTreeNode->left_child->parent = NULL;
}else if(NULL == pTreeNode->left_child && NULL != pTreeNode->right_child){
*ppTreeNode = pTreeNode->right_child;
pTreeNode->right_child->parent = NULL;
}
free(pTreeNode);
return TRUE;
}
return TRUE;
} 添加测试用例，依次添加10、15、20，然后删除数据10。
static void test5()
{
TREE_NODE* pTreeNode = NULL;
assert(TRUE == insert_node_into_tree(&pTreeNode, 10));
assert(TRUE == insert_node_into_tree(&pTreeNode, 15));