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copied!<p>This code:</p> <pre><code>cursor = new Node; cursor = begin; </code></pre> <p>Does the following:</p> <ul> <li>Create a new Node object on the stack</li> <li>Put the address of that object in variable <code>current</code></li> <li>Immediately overwrite that address with the address that <code>begin</code> contains</li> </ul> <p>i.e. all it does is leak a new <code>Node</code>. <code>cursor</code> and <code>begin</code> point to the same thing after that.</p> <p>Thus the line:</p> <pre><code>cursor->next = begin; </code></pre> <p>Makes a loop. <code>cursor->next == begin == cursor</code>.</p> <p>Removing the <code>cursor = begin;</code> line, and returning cursor will do what you want. The Node created with <code>new Node</code> will be the new head of the list, and the one that <code>begin</code> pointed to at the start of the function will be the second node in that list.</p> <p>Now when you want to traverse (not add to) that list, you can do something like:</p> <pre><code> Node *cursor = begin; // assuming begin is the head of your list while (cursor != 0) { // process this node cursor = cursor->next; } </code></pre> <p>And that will visit each node in your list, assuming you've built it correctly.</p> <p>A few notes:</p> <ul> <li><p>The code that calls this function should probably look something like:</p> <pre><code>list = add_node(list, ...); </code></pre> <p>If you don't have that, you'll not get what you want.</p></li> <li><p>If the address you see in <code>begin</code> looks <em>very</em> different from the one returned by <code>new</code>, you're could be doing something wrong, i.e. <code>begin</code> could point at a stack address. Don't put objects from your stack on the list, make sure you all allocate them with <code>new</code>. (If <code>begin</code> points to a global static variable, that's fine - but make sure you don't <code>delete</code> it).</p></li> <li><p>Unless you actually <em>need</em> a dummy node, I'd suggest you remove that too - it makes your <code>add_node</code> function more complex than it needs to be.</p></li> </ul> <p>Here's a skeleton of how you would do it without that special dummy node (incomplete code):</p> <pre><code>Node *add_node(Node *list, ...) { Node *new_node = new Node; new_node->next = list; // fill in other properties return new_node; } </code></pre> <p>And to use this:</p> <pre><code>int foo() { Node *list = 0; // or nullptr for C++11 list = add_node(list, ...); // add item 1 list = add_node(list, ...); // add item 2 list = add_node(list, ...); // add item 3 ... </code></pre>

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