C++/List/list find

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Find element in a list

<source lang="cpp">

/* 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 <list>
  3. include <algorithm>

using namespace std; int main() {

   list<int> coll;
   list<int>::iterator pos;
   // insert elements from 20 to 40
   for (int i=20; i<=40; ++i) {
       coll.push_back(i);
   }
   /* find position of element with value 3
    * - there is none, so pos gets coll.end()
    */
   pos = find (coll.begin(), coll.end(),    // range
               3);                          // value
   
   /* reverse the order of elements between found element and the end
    * - because pos is coll.end() it reverses an empty range
    */
   reverse (pos, coll.end());
   // find positions of values 25 and 35
   list<int>::iterator pos25, pos35;
   pos25 = find (coll.begin(), coll.end(),  // range
                 25);                       // value
   pos35 = find (coll.begin(), coll.end(),  // range
                 35);                       // value
   /* print the maximum of the corresponding range
    * - note: including pos25 but excluding pos35
    */
   cout << "max: " << *max_element (pos25, pos35) << endl;
   // process the elements including the last position
   cout << "max: " << *max_element (pos25, ++pos35) << endl;

} /* max: 34 max: 35

*/
       
 </source>


Find the maximum element in a range in a list

<source lang="cpp">

/* 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 <list>
  3. include <algorithm>

using namespace std; int main() {

   list<int> coll;
   list<int>::iterator pos;
   // insert elements from 20 to 40
   for (int i=20; i<=40; ++i) {
       coll.push_back(i);
   }
   /* find position of element with value 3
    * - there is none, so pos gets coll.end()
    */
   pos = find (coll.begin(), coll.end(),    // range
               3);                          // value
   
   /* reverse the order of elements between found element and the end
    * - because pos is coll.end() it reverses an empty range
    */
   reverse (pos, coll.end());
   // find positions of values 25 and 35
   list<int>::iterator pos25, pos35;
   pos25 = find (coll.begin(), coll.end(),  // range
                 25);                       // value
   pos35 = find (coll.begin(), coll.end(),  // range
                 35);                       // value
   /* print the maximum of the corresponding range
    * - note: including pos25 but excluding pos35
    */
   cout << "max: " << *max_element (pos25, pos35) << endl;
   // process the elements including the last position
   cout << "max: " << *max_element (pos25, ++pos35) << endl;

} /* max: 34 max: 35

*/
       
 </source>