如何在 C++ 中正确删除链表的节点

I feel as if I am not actually deleting the node and freeing up memory. I think I am just moving pointers around so when I print the linked list the list doesn't print the element I deleted. So my question is am I actually deleting the node or am I just simply rearranging the pointers so it looks like I am deleting the nodes(Essentially just breaking the links but not deleting the node)? Thank you for any help.

void SLL::deleteNode(int target){
Node *current = new Node;
Node *previous = new Node;

for (current = front->next, previous = front; current != NULL; current = current->next, previous=previous->next){
    if (previous->data == target && previous == front){
        front = previous->next;
        delete[] previous;
        return;
    //This if statement deletes the element if its the front
    }

    else {

        if (previous->data == target && previous->next == NULL){
            previous = NULL;
            delete[] current;
            return;
        //This if statement deletes the node if it is the back
        }


        else if (current->data==target)
        {
            previous->next = current->next;
            delete[] current;
            return;
        //This if statement deletes a node if it is in the middle
        }
    }
    }

    delete[] current;
    delete[] previous;
}

推荐答案

Node *current  = new Node;
Node *previous = new Node;

此代码会导致内存泄漏 - 您永远不会删除此内存.您可以在不分配内存的情况下声明指针:

Node *current  = nullptr;
Node *previous = nullptr;

Node* pCur  = pHead;
Node* pPrev = pCur;

while (pCur && pCur->data != target) {
    pPrev = pCur;
    pCur  = pCur->next;
}

if (pCur==nullptr)  // not found
   return NOT_FOUND;

if (pCur == pHead) {   // first element matches
    pHead = pCur->next;
} else {
    pPrev->next = pCur->next;
}

// pCur now is excluded from the list

delete pCur;     // deallocate its memory

Node **pp = &pHead;
while (*pp && (*pp)->data != target)
    pp = &(*pp)->next;

if (*pp)
{
    Node *victim = *pp;
    *pp = victim->next;
    delete victim;
}