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POCreating an empty instance of a class
 

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    <p>Ok, I have a class <code>Set</code> who keeps a <code>vector&lt;int&gt;</code> as its data payload. It has a constructor that accepts a <code>string</code> as a parameter such as <code>Set test = Set("1 2 3 4 5 6");</code> I have a function that reads the line, and parses it into a <code>vector&lt;int&gt;</code> from there I can perform operations on the <code>Set</code>. The problem comes when <code>Set test = Set("");</code> is called, my constructor cannot make a <code>Set</code> because it has nothing to parse. My program can't go anywhere. I've tried putting if else statements in the constructor but how can I declare an empty <code>set</code>?</p> <p>Right now I get a segmentation fault.</p> <pre><code>#include "Set.h" using namespace std; /*************************************************************************************** * Constructors and Destructors **/ Set::Set(){ } Set::Set(string inputString) { if(inputString != ""){ readLine(inputString); } else{ //I've tried several things here, none of which work. } } Set::~Set(){ } /*************************************************************************************** * readLine function * * This function takes in a string, takes the next int, and stores in in a vector. * * Parameters: string, the string to be parsed. * **/ void Set::readLine(string inString){ ScanLine scanLine; scanLine.openString(inString); while(scanLine.hasMoreData()){ addToSet(scanLine.nextInt()); } } /*************************************************************************************** * addToSet function * * This function takes in a int that is an element and adds it to "this" Set. * * Parameters: int, the element to be added. * Return: int, the value that was added. * **/ int Set::addToSet(int element){ int returnValue = -1; if(!containsElement(element)){ this-&gt;theSet.push_back(element); returnValue = element; } return returnValue; } </code></pre>
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    1. USTrevor Hutto
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    1. COWhat's wrong with the code you posted? What makes you believe that you need to replace `//I've tried several things here, none of which work.` with anything?
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      1. USOswald
    2. COIf I leave off the else statement, I get segmentation fault 11. Which made me think I needed an else.
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      1. USTrevor Hutto
    3. COThe code you posted is not responsible for the segmentation fault. Provide a [short, self-contained, correct example](http://sscce.org).
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