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POInitializing nodes in a list from a .txt file
 

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  1. POInitializing nodes in a list from a .txt file
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    <p>Currently have a custom Linked List class that works well.</p> <p>I implemented a function that can export all the contents of each Node to a .txt file when the program exits. I now want to import that same file to re-populate the list at the program start, and that's where I ran into some difficulty. (the <code>&gt;&gt;</code> and <code>&lt;&lt;</code> operators are overloaded) and this entire linked-list class is specific to this program and not really meant to be re-usable. </p> <p>my export function:</p> <pre><code>void List::exportData(){ Node *currentPtr = Head; cout&lt;&lt;"Saving Data..."&lt;&lt;endl; ofstream fileOut("stock_transaction_history.txt"); while (currentPtr != 0){ fileOut&lt;&lt; currentPtr-&gt;symbol &lt;&lt; " " &lt;&lt;currentPtr-&gt;shares&lt;&lt;endl; currentPtr = currentPtr-&gt;next; //iterates down the list } } </code></pre> <p>Now I'm completely stuck on the import data feature. I also have a function <code>addToBack((Node *newPtr)</code> at my disposal if necessary.</p> <pre><code>void List::importData(){ Node *currentPtr ifstream stockIn("stock_transaction_history.txt"); } stockIn &gt;&gt; currentPtr-&gt;symbol &gt;&gt;currentPtr -&gt;shares;//(Node(tempSymbol, num)); currentPtr = currentPtr-&gt;next; stockIn.close(); </code></pre> <p>}</p> <p>I'm thinking I might have to call <code>addToBack</code> via something along the lines of <code>Node *tempPtr=new Node();</code> or just call the generic <code>data</code> portion of my node?</p> <p>here is my <code>node.h</code></p> <pre><code>class Node { private: friend class List; string symbol; int shares; Node *next; public: Node() : next(0) { } </code></pre>
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    1. USStaypuft
    1. USStaypuft
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    1. COYes, presumably it would help if your list had an interface to add new nodes to it!
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      1. USKerrek SB
    2. COhow can your `importData` possibly work, you have to know before hand all the nodes that can exist in the list!?! better to have a `push_back` with a new node... so steps are construct new node, read from stream, push this back. Look at how this would work with a `std::list`.
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      1. USNim
    3. COObviously, I have to eliminate that While statement too, as the list will always be empty to begin with.
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      1. USStaypuft
 

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