C++/List/list splice

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Insert all elements of list1 before the first element with value 3 of list2

  
 
/* 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.
 */
#include <iostream>
#include <list>
#include <algorithm>
#include <iterator>
using namespace std;
void printLists (const list<int>& l1, const list<int>& l2)
{
    cout << "list1: ";
    copy (l1.begin(), l1.end(), ostream_iterator<int>(cout," "));
    cout << endl << "list2: ";
    copy (l2.begin(), l2.end(), ostream_iterator<int>(cout," "));
    cout << endl << endl;
}
int main()
{
    // create two empty lists
    list<int> list1, list2;
    // fill both lists with elements
    for (int i=0; i<6; ++i) {
        list1.push_back(i);
        list2.push_front(i);
    }
    printLists(list1, list2);
    // insert all elements of list1 before the first element with value 3 of list2
    // - find() returns an iterator to the first element with value 3
    list2.splice(find(list2.begin(),list2.end(),  // destination position
                      3),
                 list1);                          // source list
    printLists(list1, list2);
}
 /* 
list1: 0 1 2 3 4 5
list2: 5 4 3 2 1 0
list1:
list2: 5 4 0 1 2 3 4 5 3 2 1 0

 */


List Splice

  
#include <list>
#include <string>
#include <iostream>
using namespace std;
int main(int argc, char** argv)
{
  list<string> dictionary, bWords;
  dictionary.push_back("A");
  dictionary.push_back("B");
  dictionary.push_back("C");
  dictionary.push_back("D");
  dictionary.push_back("E");
  dictionary.push_back("F");
  bWords.push_back("G");
  bWords.push_back("H");
  bWords.push_back("I");
  list<string>::iterator it;
  int i;
  for (it = dictionary.begin(), i = 0; i < 3; ++it, ++i);
  dictionary.splice(it, bWords);
  for (it = dictionary.begin(); it != dictionary.end(); ++it) {
    cout << *it << endl;
  }
  return (0);
}


Move first element to the end

  
 
/* 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.
 */
#include <iostream>
#include <list>
#include <algorithm>
#include <iterator>
using namespace std;
void printLists (const list<int>& l1, const list<int>& l2)
{
    cout << "list1: ";
    copy (l1.begin(), l1.end(), ostream_iterator<int>(cout," "));
    cout << endl << "list2: ";
    copy (l2.begin(), l2.end(), ostream_iterator<int>(cout," "));
    cout << endl << endl;
}
int main()
{
    // create two empty lists
    list<int> list1, list2;
    // fill both lists with elements
    for (int i=0; i<6; ++i) {
        list1.push_back(i);
        list2.push_front(i);
    }
    printLists(list1, list2);
    // move first element to the end
    list2.splice(list2.end(),        // destination position
                 list2,              // source list
                 list2.begin());     // source position
    printLists(list1, list2);
}
 /* 
list1: 0 1 2 3 4 5
list2: 5 4 3 2 1 0
list1: 0 1 2 3 4 5
list2: 4 3 2 1 0 5

 */


Use list.splice() to remove elements in a list and insert at end of values

  
 
#include <iostream>
using std::cout;
using std::endl;
#include <list>      // list class-template definition
#include <algorithm> // copy algorithm
#include <iterator>  // ostream_iterator
int main()
{
   int array[ 4 ] = { 2, 6, 4, 8 };
   std::list< int > values;      // create list of ints
   std::list< int > otherValues; // create list of ints
   std::ostream_iterator< int > output( cout, " " );
   // insert items in values
   values.push_front( 1 );
   values.push_front( 3 );
   values.push_back( 4 );
   values.push_back( 2 );
   cout << "values contains: ";
   std::copy( values.begin(), values.end(), output );
   otherValues.insert( otherValues.begin(), array, array + 4 );
   values.splice( values.end(), otherValues );
   cout << "\n\nvalues contains: ";
   std::copy( values.begin(), values.end(), output );
   cout << endl;
   return 0;
}
 /* 
values contains: 3 1 4 2
values contains: 3 1 4 2 2 6 4 8
 */