C++/Vector/vector reserve

Reserve memory for five elements to avoid reallocation

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/* The following code example is taken from the book

* "The C++ Standard Library - A Tutorial and Reference"
* by Nicolai M. Josuttis, Addison-Wesley, 1999
*
* (C) Copyright Nicolai M. Josuttis 1999.
* Permission to copy, use, modify, sell and distribute this software
* is granted provided this copyright notice appears in all copies.
* This software is provided "as is" without express or implied
* warranty, and with no claim as to its suitability for any purpose.
*/

1. include <iostream>
2. include <vector>
3. include <string>
4. include <algorithm>
5. include <iterator>

using namespace std; int main() {

   // create empty vector for strings
   vector<string> sentence;
   // reserve memory for five elements to avoid reallocation
   sentence.reserve(5);
   // append some elements
   sentence.push_back("Hello,");
   sentence.push_back("how");
   sentence.push_back("are");
   sentence.push_back("you");
   sentence.push_back("?");
   // print elements separated with spaces
   copy (sentence.begin(), sentence.end(),
         ostream_iterator<string>(cout," "));
   cout << endl;

} /* Hello, how are you ?

*/        
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