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POc-style string sorting with sort and qsort
 

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    <p>I'm trying to use both sort and qsort to sort a c-style string and them see which of them is better, so I've written this code, but it is not working , so can you please tell me what is wrong with it. thanks in advance.</p> <pre><code>#include &lt;iostream&gt; #include&lt;vector&gt; #include&lt;cstdlib&gt; #include&lt;algorithm&gt; #include&lt;cstring&gt; #include&lt;chrono&gt; #include&lt;string&gt; #include&lt;sstream&gt; using namespace std; using namespace std::chrono; void bvect(vector&lt;double&gt; &amp;vec, int num) { auto gen = bind(normal_distribution&lt;double&gt;(15,4.0),default_random_engine()); for(int i=0; i&lt;num; ++i) vec.push_back(gen()); } char* converttostring(int number) { stringstream ss; ss &lt;&lt; number; return (ss.c_str()); } int cst_cmp(const void *one, const void *two) { char a = *((char*)one); char b = *((char*)two); return strcmp(a, b); } //Generated random strings void textvect(vector&lt;string&gt; &amp;vec, int num) { srand(time(NULL)); for(int i=0; i&lt;num; ++i) vec.push_back(converttostring(rand()%num +1)); } void displayvector(vector&lt;char*&gt;vect) { for (int i=0; i&lt;vect.size(); ++i){ for (int j=0; j&lt;strlen(vect[i]); ++j) cout&lt;&lt;vect[i][j]; cout&lt;&lt;endl; } } int main(){ int sz=100000; vector&lt;char*&gt;text1, text2; textvect(text1, sz); text2.resize(text1.size()); copy(text1.begin(),text1.end(),text2.begin()); // qsort() string auto t1 = system_clock::now(); qsort(&amp;text1[0], text1.size(), sizeof(char*), cst_cmp); auto t2 = system_clock::now(); auto dms = duration_cast&lt;milliseconds&gt;(t2-t1); cout &lt;&lt; "string qsort() took " &lt;&lt; dms.count() &lt;&lt; " milliseconds\n"; // sort() string auto t3 = system_clock::now(); std::sort(text2.begin(), text2.end()); auto t4 = system_clock::now(); auto dms1 = duration_cast&lt;milliseconds&gt;(t4-t3); cout &lt;&lt; "string sort() took " &lt;&lt; dms1.count() &lt;&lt; " milliseconds\n"; return 0; } </code></pre>
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    1. COCan you be more specific than it's not working? What does it do? Crash? Not compile? The output is wrong?
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    2. COConverttostring is returning a pointer to a local. That is not going to work. It should perhaps return string not char*.
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    3. CO`std::generate_n(std::back_inserter(vec), num, gen);`
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      1. USoldrinb
 

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