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POGarbage Result! C++ LinkedList
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copied!<p>Given the code in main:</p> <pre><code>// main.cpp wineries->insert(winery("Lopez Island Vinyard", "San Juan Islands", 7, 95)); </code></pre> <p>Two things will happen:</p> <ol> <li><p>The winery constructor is invoked where I have intialized the winery private members:</p> <pre><code>//winery.cpp winery::winery(const char * const name, const char * const location, const int acres, const int rating) : name( new char[strlen(name)+1] ) , location( new char[strlen(location)+1] ) , acres( 0 ), rating( 0 ) { } </code></pre> <p>When it is finished, the result of the <code>this</code> pointer has a garbage value. Why is this? Am I not initializing correctly?</p></li> <li><p>After the winery constructor dies, we go to the <code>list::insert( const winery &winery )</code> function:</p> <pre><code>void list::insert(const winery& winery) { node *NodePtr = new node( winery ); // NodePtr->item has the garbage. NodePtr->item = winery; } list::node::node( const winery& winery ) { // This works because I have a default constructor for the winery object // and *only* for that reason... // How can I use the node constructor without having to use a default constructor for the winery class? } </code></pre> <p>Why am I getting garbage as a result of the values passed to the winery constructor?</p> <p>The winery public member functions are as follows, where <code>name</code>, <code>location</code>, <code>acres</code>, and <code>rating</code> are all private members to the winery class.</p> <pre><code>winery::winery() { // do nothing default constructor // only here so I can add the &winery to the node constructor.. } winery::~winery() { delete location; delete name; // your code here } const char * const winery::getName() const { //winery *wine_t = new winery(); const char cName[5] = "four"; // just to see if it still gives garbage.. return cName } const char * const winery::getLocation() const { // return one of winery's private members. // It *will* crash when this function is called. // *That* might be the issue with **garbage values** return location; } </code></pre> <p>Without these functions having parameters, it makes it difficult to transfer the attributes over to a wineryPtr object, and then it would be logical to add the entire winery object to the linkedlist...</p> <pre><code>// list.h #ifndef _LIST_ #define _LIST_ #include <ostream> #include "winery.h" using namespace std; class list { public: list(void); // constructor virtual ~list(void); // destructor ... void insert(const winery& winery); winery * const find(const char * const name) const; private: struct node { node(const winery& winery); // constructor winery item; node * nextByName; node * nextByRating; }; node * headByName; node * headByRating; }; #endif // _LIST_ </code></pre></li> </ol> <p>My questions are a little scattered, and I hope someone out there has the time to help!</p>

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