私が抱えている問題は、ツリーがノードを 1 回だけ正常に削除できることです。さらに削除しようとすると、セグメンテーション違反 (コア ダンプ) エラーでクラッシュします。障害が発生している正確な場所を特定できないようですが、メモリの割り当てと割り当て解除で間違っているはずです。
これが私の挿入、削除、削除ヘルパー、およびリーフです（削除内で呼び出されるため）：
入れる：
/*********************************************************
Function: insert
Arguments: const T &x (a T variable)
Returns: void
Notes: If the tree is empty, the function will set the node
as the root. Otherwise, it will look for the appropiate
place (in terms of a BST) to place it as long as its data
is not already existent inside the tree.
*********************************************************/
template<class T> void binSTree<T>::insert(const T &x)
{
BinTreeNode *newnode, *current, *parentOfCurrent; /* newnode will be the inserted node, current and parentOfCurrent will be traversing the while loop to find an appropiate space to insert */
newnode = new BinTreeNode; /* allocates storage space */
newnode->info = x; /* sets newnode's data equal to x */
newnode->left = newnode->right = NULL; /* sets newnode's left and right children equal to NULL */
if (root == NULL) { /* if the tree is empty, it will place newnode on the root */
root = newnode;
cout << "added to root\n";
return; }
current = root; /* sets current at the root */
while(current != NULL) { /* while current is not NULL, it will search for a place to insert the new node */
parentOfCurrent = current; /* sets the parent equal to current */
if(current->info == x) /* if the variable is found inside the tree, then it will error and exit */
{
cout << x << " already exists in tree. Duplicates not allowed!\n";
return;
}
else if(current->info > x) /* otherwise, if the variable is less than the data on the tree currently, it will move left */
current = current->left;
else /* otherwise, if the variable is greater than the data on the tree currently, it will move right */ current = current->right;
}
/* the new node is placed where current would be in */
if (parentOfCurrent->info > x)
parentOfCurrent->left = newnode;
else
parentOfCurrent->right = newnode;
}
削除および privRemove:
template <class T> bool binSTree<T>::remove(const T &x)
{
BinTreeNode *current, *parentOfCurrent; /* current for tranversing the tree in the while loop and parentofCurrent to help */
bool found = false; /* the booleans that is to be returned */
if (root == NULL) { /* Checks if the tree is empty, if it is, it returns found (false) and exits */
return found;
}
current = root; /* sets current equal to root */
while(current != NULL) /* loops repeats until current is equal to NULL */
{
if(current->info == x) { /* if the current data from the tree is equal tox, then it breaks the loop and sets found equal to true */
found = true;
break;
}
else { /* otherwise, it will search for the next place to go in the tree */
parentOfCurrent = current; /* parentOfCurrent is set to current before current is set to one of its children */
if(current->info > x) /* if x is less than the data on current, then it will move left */
current = current->left;
else /* if x is greater than the data on current, then it will move right */
current = current->right;
}
}
if(found == true) { /* if it was found, it will pass current via the parent to the private remove function */
if (current == root)
privRemove(root);
else if (parentOfCurrent->info > x) { /* if current is to the left of the parent */
found = leaf( parentOfCurrent->left );
if(found == true)
privRemove(parentOfCurrent->left);
}
else { /* if current is to the right of the parent */
found = leaf( parentOfCurrent->left );
if(found == true)
privRemove(parentOfCurrent->right);
}
}
return found;
}
/*********************************************************
Function: privRemove
Arguments: BinTreeNode* &node (the node that is to be deleted)
Returns: void
Notes: This private remove function will take in the node that
is provided by the public remove function, and, after ensuring
that the node passed is not NULL, then it will delete it.
*********************************************************/
template <class T> void binSTree<T>::privRemove(BinTreeNode* &node)
{
BinTreeNode *temp; /* initializes temp in order to hold the information of node */
if(root != NULL ) /* if the node is not NULL */
{
temp = node;
delete node;
node = temp;
}
}
葉：
/*********************************************************
Function: leaf
Arguments: BinTreeNode* node
Returns: boolean
Notes: This function will check if the node in the argument
is a leaf by checking if both of its children are NULL. If
they are, it returns true. Otherwise, it returns false.
*********************************************************/
template <class T> bool binSTree<T>::leaf(BinTreeNode* node) const
{
bool isLEaf = false; /* the boolean variable it is to return */
if(node->left == NULL && node->right == NULL) /* checks if the node has no children */
isLEaf = true; /* if it does, it sets isLEaf equal to true */
return isLEaf; /* after going through the if statement, it returns the variable isLeaf */
}
私のノードはクラス ヘッダー内で宣言された構造体であり、変数 root は BinTreeNode* root; の形式で保護された変数として宣言されていることに注意してください。binSTree コンストラクター内で NULL として初期化されます。また、葉の削除のみ許可されています。