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POpolymorphism concept
 

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    <p>I'm getting a "Segmentation Fault" while running this program. Please differentiate between the below two programs</p> <pre><code>class xxx{ public: virtual void f(){cout&lt;&lt;"f in xxx"&lt;&lt;endl;} //virtual function virtual void g(){cout&lt;&lt;"g in xxx"&lt;&lt;endl;} //virtual function }; class yyy{ //yyy has no relation with xxx at this context public: virtual void f(){cout&lt;&lt;"f in yyy"&lt;&lt;endl;} //virtual function but no relation with xxx class void g(){cout&lt;&lt;"g in yyy"&lt;&lt;endl;} }; int main(int argc, char *argv[]) { xxx x1,*x; yyy y1; x=&amp;x1; x-&gt;f(); x-&gt;g(); x=(xxx*) &amp;y1; //one class pointer containing another class object address x-&gt;f(); x-&gt;g(); } </code></pre> <p><strong>- Output</strong></p> <pre><code>f in xxx g in xxx f in yyy Segmentation fault </code></pre> <p>But according to polymorphism concept with the same problem </p> <pre><code>class xxx{ public: virtual void f(){cout&lt;&lt;"f in xxx"&lt;&lt;endl;} //virtual function virtual void g(){cout&lt;&lt;"g in xxx"&lt;&lt;endl;} //virtual function }; class yyy:public xxx{ //yyy is derived from xxx public: virtual void f(){cout&lt;&lt;"f in yyy"&lt;&lt;endl;} void g(){cout&lt;&lt;"g in yyy"&lt;&lt;endl;} }; int main(int argc, char *argv[]) { xxx x1,*x; yyy y1; x=&amp;x1; x-&gt;f(); x-&gt;g(); x=(xxx*) &amp;y1; //parent class pointer having derived class address x-&gt;f(); x-&gt;g(); } </code></pre> <p><strong>- Output</strong></p> <pre><code>f in xxx g in xxx f in yyy g in yyy </code></pre>
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    1. USthegrinner
    1. USSantosh Sahu
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    1. COYou don't need to bother casting it. Just do: x = &y1;
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      1. USJamin Grey
    2. COwhat's the question?
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      1. USCheers and hth. - Alf
    3. CODear Jamin Grey.. Got Error while trying your idea... x=&y1; // error: cannot convert âyyy*â to âxxx*â in assignment thanks...
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      1. USSantosh Sahu
 

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