Databases
StackOverflow2013
Postsdbo
POLinkedList copy constructor implementation details
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POLinkedList copy constructor implementation details
    primarykey
    data
    text
    <p>I'm starting to learn C++ and as an exercise decide to implement a simple <code>LinkedList</code> class (Below there is part of the code). I have a question regarding the way the copy constructor should be implemented and the best way the data on the original <code>LinkedList</code> should be accessed.</p> <pre><code> template &lt;typename T&gt; class LinkedList { struct Node { T data; Node *next; Node(T t, Node *n) : data(t), next(n) {}; }; public: LinkedList(); LinkedList(const LinkedList&amp;); ~LinkedList(); //member functions int size() const; //done bool empty() const; //done void append(const T&amp;); //done void prepend(const T&amp;); //done void insert(const T&amp;, int i); bool contains(const T&amp;) const; //done bool removeOne(const T&amp;); //done int removeAll(const T&amp;); //done void clear(); //done T&amp; last(); //done const T&amp; last() const; //done T&amp; first(); //done const T&amp; first() const; //done void removeFirst(); //done T takeFirst(); //done void removeLast(); T takeLast(); //delete when finished void print(); //end delete //operators bool operator ==(const LinkedList&lt;T&gt; &amp;other) const; //done bool operator !=(const LinkedList&lt;T&gt; &amp;other) const; //done LinkedList&lt;T&gt;&amp; operator =(const LinkedList&lt;T&gt; &amp;other); //done private: Node* m_head; Node* m_tail; int m_size; }; template&lt;typename T&gt; LinkedList&lt;T&gt;::LinkedList() : m_head(0), m_tail(0), m_size(0) { } ... </code></pre> <p>Should my copy constructor access the data on each node of the original <code>LinkedList</code> directly?</p> <pre><code>template&lt;typename T&gt; LinkedList&lt;T&gt;::LinkedList(const LinkedList&amp; l) { m_head = 0; m_tail = 0; m_size = 0; Node *n = l.m_head; // construct list from given list while(n) { append(n-&gt;data); n = n-&gt;next; } } </code></pre> <p>Or should I access the data through the corresponding accessor? (I know that I don't have the accessor(s) defined).</p> <p>Also, I intend to create a custom iterator so that it can be possible to iterate over the <code>LinkedList</code>. Should I use in the copy constructor to access the data on each node? </p> <p>Another question (completely off-topic, I know), when and/or why should we declare a pointer to a <code>LinkedList</code></p> <pre><code>LinkedList&lt;int&gt; *l = new LinkedList&lt;int&gt;(); </code></pre> <p>instead of</p> <pre><code>LinkedList&lt;int&gt; l; </code></pre>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USBill the Lizard
    1. USbruno
    plurals
    1. PL
      singulars
      1. LTLinked
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POLinkedList copy constructor implementation details
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. POLinkedList copy constructor implementation details
      1. This table or related slice is empty.
      1. VTUpMod
    3. VO
      singulars
      1. POLinkedList copy constructor implementation details
      1. This table or related slice is empty.
      1. VTUpMod
    1. This table or related slice is empty.
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload