}
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;
}
free(pTreeNode);
return TRUE;
}
return TRUE;
} 我们的代码明显越来越长，我们要保持耐心。此时，该是我们添加新测试用例的时候了。
static void test3()
{
TREE_NODE* pTreeNode = NULL;
pTreeNode = create_tree_node(10);
assert(TRUE == delete_node_from_tree(&pTreeNode, 10));
assert(NULL == pTreeNode);
}
static void test3()
{
TREE_NODE* pTreeNode = NULL;
pTreeNode = create_tree_node(10);
assert(TRUE == delete_node_from_tree(&pTreeNode, 10));
assert(NULL == pTreeNode);
}
2.2 删除根数据时，只有左子树节点，没有右子树节点
/*
*
* 10 ======> 5
* / \ / \
* 5 NULL 3 NULL
* /
* 3
*/
/*
*
* 10 ======> 5
* / \ / \
* 5 NULL 3 NULL
* /
* 3
*/ 很明显，我们只需要把用左子树节点代替原来的根节点即可。
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;
}
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;
}
free(pTreeNode);
return TRUE;
}
return TRUE;
}
这个时候，我们可以添加新的测试用例，分别添加10、5、3，然后删除10。
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 == inse