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    <p>Very simply, you could read the file as I have described below.</p> <pre><code>void List::importData(const char *filePath) { // open the file. std::ifstream file(filePath); // storage for the values read from the stream. std::string symbol; int shares; // here we read the symbol from the file stream, with "file &gt;&gt; symbol". the // return value of that expression is the stream 'file', so we can chain // that to reading the share count with "file &gt;&gt; symbol &gt;&gt; shares". notice // that we use this in a conditional - this is because the stream will // evaluate to 'true' if there is more data to read, or 'false' otherwise. while ((file &gt;&gt; symbol &gt;&gt; shares)) { // create the new node addToBack(symbol, shares); } } </code></pre> <p>A few potential improvements to your <code>List</code>/<code>Node</code> arrangement. What i've given below ignores the problems of <strong>copy assignment</strong> and <strong>copy construction</strong>. As it stands, it'll blow up if you do either of these things - its left as an exercise to fix. But ultimately, i'd recommend using an <code>std::list&lt;StockItem&gt;</code>, where <code>StockItem</code> contains just the <code>symbol</code> and <code>share_count</code>.</p> <pre><code>#include &lt;fstream&gt; #include &lt;memory&gt; // the node class used in the list. note that I have not declared the list // to be a friend of the node. its needed as the data members are public. if // you dont want the data to be public (e.g. you want to enforce certain // operations) make them private, and provide accessor functions. in this case // StockNode is a struct, making the data members public by default. struct StockNode { std::string mSymbol; int mShares; StockNode *mNext; // custom constructor, which populates the symbol and shares. StockNode(const std::string&amp; symbol, int shares) : mSymbol(symbol), mShares(shares), mNext(0) { } }; class StockList { // we store the head AND the tail of the list. storing the tail allows for // fast appends. StockNode *mHead; StockNode *mTail; public: // we override the default constructor to initialize the head/tail pointers // to 0 (null). StockList() : mHead(0), mTail(0) { } // destructor - since we are using raw pointers, we need to manage the // freeing of the StockNodes ourselfs (again, if we used a // std::list&lt;StockNode&gt; we could have avoided this. ~StockList() { clear(); } void clear() { StockNode *node = mHead; // while we havent reached the end of the list. while (node) { // find the next element StockNode *temp = node-&gt;mNext; // free the memory for the current element. delete node; // set node to the next element in the list. node = temp; } // reset the pointers mHead = 0; mTail = 0; } // appends a node to the list. i have called it push_back in line with the // standard library implementation std::list (which you would normally use // here, but it looks like this is homework). notice that the parameter // is not a pointer, but a std::auto_ptr. look up the documentation for it // to see exactly how it works. its not *required* here, but i use it so // the interface documents that we are taking ownership of the node. void push_back(std::auto_ptr&lt;StockNode&gt; stockNode) { // notice below the calls to "release", this stops the std::auto_ptr // managing the memory - so it doesn't free the memory when we still // need it. if (mTail) { // the tail is set, write the new value. mTail-&gt;mNext = stockNode.release(); mTail = mTail-&gt;mNext; } else { // no tail set means this is the first element, set the head and // the tail. mHead = stockNode.release(); mTail = mHead; } } // ... implement other methods for looking up StockNodes, etc... void exportData(const std::string&amp; filePath) const { std::ofstream file(filePath.c_str()); for (StockNode *node = mHead; node; node = node-&gt;mNext) { // note that i have used '\n' instead of std::endl. this is // because std::endl prints the '\n' and flushes the stream // as we are writing to file, i figure it'll be a little quicker // if it doesnt flush to disk after every line. file &lt;&lt; node-&gt;mSymbol &lt;&lt; " " &lt;&lt; node-&gt;mNext &lt;&lt; '\n'; } } void importData(const std::string&amp; filePath) { std::ifstream file(filePath.c_str()); std::string symbol; int shares; while ((file &gt;&gt; symbol &gt;&gt; shares)) { push_back(std::auto_ptr&lt;StockNode&gt;(new StockNode(symbol, shares))); } } }; </code></pre>
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