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POC++ Huffman Tree and Pointers
 

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    <p>I am creating a Huffman Tree and to do so I started with making a Min Heap. The heap is set up and works sorting the values by frequency in the document but my problem comes when I try to start creating the tree.</p> <p>I am popping the top two items off the heap and putting a node above them and reinserting into the heap. The heap is array based so it does not touch the *left and *right pointers of the nodes. When the heap is down to only one node however both it's left and right node pointers are null so I believe it may be an issue with my pointers...? I am new to c++ from java for give my dumb mistakes.</p> <pre><code> while(theHeap.getheapSize() &gt; 1) { Node top; Node *min1=new Node(theHeap.topandPop()); Node *min2=new Node(theHeap.topandPop()); top.left=min1; top.right=min2; top.freq=min1-&gt;freq+min2-&gt;freq; theHeap.insert(top); } Node r=theHeap.topAndPop(); //null pointers for left and right children -------------------------------------- //code for heap. arr is in the header file is Node *arr; void Heap::insert(Node c) { if (heapSize != arrSize) { heapSize=heapSize+1; arr[heapSize - 1] = c; //does this call copy constructor??? percolateUp(heapSize - 1); } } void Heap::percolateUp(int nodeIndex) { int parentIndex; Node tmp; if (nodeIndex != 0) { parentIndex = getParentPos(nodeIndex); if (arr[parentIndex].freq &gt; arr[nodeIndex].freq) { tmp = arr[parentIndex]; arr[parentIndex] = arr[nodeIndex]; arr[nodeIndex] = tmp; percolateUp(parentIndex); } } } </code></pre>
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    1. USBill the Lizard
    1. USWestin
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    1. COHave you considered using `std::priority_queue` for the heap?
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      1. USJames McNellis
    2. COIt's a homework assignment and we are not allowed to use standard library.
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      1. USWestin
    3. COJust to make sure: `top` goes out of scope, so hopefully `insert()` calls a copy constructor instead of just taking an address?
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      1. USReinderien
 

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