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POiterating through pointer arrays and displaying
 

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  1. POiterating through pointer arrays and displaying
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    <p>ii'm having some issues understanding pointer arrays, see the following simplified code</p> <pre><code>#include &lt;string&gt; #include &lt;iostream&gt; using namespace std; //holds two different datatypes template &lt;typename A, typename B&gt; class data { public: A dataA; B dataB; data(){} data* add(A dataA, B dataB){ this-&gt;dataA = dataA; this-&gt;dataB = dataB; return this; } }; //stores an array of the data template &lt;typename A, typename B&gt; class container { data&lt;A, B&gt; **dataArray; int ammount; public: typedef data&lt;A, B&gt; * iterator; container(){ //create dynamic array of pointers dataArray = new data&lt;A, B&gt;*[5]; ammount = 0; } ~container(){ for (int i = 0; i &lt;= ammount; i++) { delete dataArray[i]; } } void add(A dataA, B dataB){ data&lt;A, B&gt; *newItem; if (ammount &lt;= 5){ newItem = new data&lt;A, B&gt;(); dataArray[ammount] = newItem-&gt;add(dataA, dataB); ammount++; } } //basic iterators iterator begin(){ return *dataArray; } iterator end(){ return dataArray[5]; } }; void main(){ string somestuff[] = { "one", "two", "three", "four", "five" }; container&lt;string, int&gt; foo; for (int i = 0; i &lt; 5; i++){ foo.add(somestuff[i], i); } container&lt;string, int&gt;::iterator it = foo.begin(); // why cant i just iterate through each item in the array for (it; it &lt; foo.end(); it++) { cout &lt;&lt; "Data A : " &lt;&lt; it-&gt;dataA &lt;&lt; " Data B : " &lt;&lt; it-&gt;dataB &lt;&lt; "\n"; } } </code></pre> <p>the issue is in main, I cant move through the array when displaying. Am I looking at this problem all wrong ?</p> <p>ps I am aware STL containers would be better here but I need to understand this specific scenario, i.e. a dynamic array(not using vector) of pointers to objects</p> <p>**edit i have added a few output statements to show what I am trying to achieve</p> <p>output is </p> <pre><code>Adding data Added Data at address : 00779218 Added Data at address : 00779458 Added Data at address : 007794B8 Added Data at address : 00779560 Added Data at address : 00779730 Printing data The address of 'it' is now: 00779218 Data A : one Data B : 0 incerementing from map.begin The address of 'it' is now: 00779238 Data A : Data B : 469784212 incerementing from map.begin The address of 'it' is now: 00779258 Data A : X Data B : -33686019 incerementing from map.begin The address of 'it' is now: 00779278 </code></pre> <p>when i am doing this </p> <pre><code>for (it; it &lt; foo.end(); it++){ cout &lt;&lt; "The address of 'it' is now: "&lt;&lt;it&lt;&lt;"\n"; cout &lt;&lt; "Data A : " &lt;&lt; it-&gt;dataA &lt;&lt; " Data B : " &lt;&lt; it-&gt;dataB &lt;&lt; "\n"; cout &lt;&lt; "incerementing from map.begin\n"; } </code></pre> <p>I need the 'it' variable top point at the next item in the dataArray, it is incrementing just not properly</p>
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