C++ Tutorial/list/list display

Материал из C\C++ эксперт
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Print all elements in a list with copy function

/* 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);
}
list1: 0 1 2 3 4 5
list2: 5 4 3 2 1 0

Print out each element in a list

/* 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>
using namespace std;
/* PRINT_ELEMENTS()
 * - prints optional C-string optcstr followed by
 * - all elements of the collection coll
 * - separated by spaces
 */
template <class T>
inline void PRINT_ELEMENTS (const T& coll, const char* optcstr="")
{
    typename T::const_iterator pos;
    std::cout << optcstr;
    for (pos=coll.begin(); pos!=coll.end(); ++pos) {
        std::cout << *pos << " ";
    }
    std::cout << std::endl;
}

int main()
{
    list<int> coll;
    // insert elements from 1 to 9
    for (int i=1; i<=9; ++i) {
        coll.push_back(i);
    }
    PRINT_ELEMENTS(coll,"initialized:                ");
}
initialized:                1 2 3 4 5 6 7 8 9

Use ostream_iterator and copy to display collection content

#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 );
   cout << "\n\notherValues contains: ";
   std::copy( otherValues.begin(), otherValues.end(), output );

   values.merge( otherValues );
   cout << "\n\nvalues contains: ";
   std::copy( values.begin(), values.end(), output );
   cout << endl;
   return 0;
}
values contains: 3 1 4 2
otherValues contains: 2 6 4 8
values contains: 2 3 1 4 2 6 4 8