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POWhy does the debugger show only one element from my array pointer?
 

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  1. POWhy does the debugger show only one element from my array pointer?
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    <p>First off: I know that <code>new</code> is the C++ way of doing this. I am simply showing that there is more than one way to reproduce this error, and both are incredibly frustrating.</p> <p>I have two forms of this source file. I'm trying to debug yet another programming assignment, but I'm not asking for help on that. Basically, I'm trying to re-implement <code>set</code> as a class with fields for size and a pointer to an <code>int</code> array. Here's the code using <code>new</code>:</p> <p>testnew.cpp</p> <pre><code>int main() { int size = 1; int *elements = new int[size]; elements[0] = 0; size++; int * temp = new int[size]; for (int i = 0; i &lt; (size - 1); i++) { temp[i] = elements[i]; } delete[] elements; temp[size] = size; elements = temp; elements[1] = 1; delete[] elements; } </code></pre> <p>and again, using the less-preferable <code>alloc</code> functions:</p> <p>testalloc.cpp</p> <pre><code>int main() { int size = 1; int * elements = (int *) malloc(sizeof(int) * size); elements[0] = 0; size++; elements =(int *) realloc(elements,size * sizeof(int)); elements[1] = 1; free(elements); } </code></pre> <p>In both cases, my goal is to create an array, and then append to it. However, in both cases, after building and running it in Visual Studio 2010, <strong>the array is not grown at all, and only has 1 "slot" for my items to go into</strong>. In VS's debugger, I have watches on the <code>elements</code> array pointer; attached is a screenshot. It is the same for both versions of the code.</p> <p><img src="https://i.stack.imgur.com/CRtuU.jpg" alt="My watches at the end of the program"> </p> <p>-- the breakpoint is at the <code>delete[]</code>/<code>free()</code> call.</p> <p>Seriously, what am I doing wrong? This has to be a logic error, and I've combed through a quarter dozen examples of both <code>malloc</code>/<code>realloc</code> and <code>new</code>, and read and re-read my textbook, and I can't see what's wrong! </p> <p>I feel like I should have a line that splits the allocated memory into an array, but doesn't the <code>new int[]</code> call do that?</p>
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