C++/STL Algorithms Modifying sequence operations/remove copy if

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Copy elements from one vector to another vector, removing elements greater than 9 in the process

 
 
#include <iostream>
using std::cout;
using std::endl;
#include <algorithm>
#include <vector>
#include <iterator>
bool greater9( int );
int main()
{
   int a[ 10 ] = { 10, 2, 10, 4, 16, 6, 14, 8, 12, 10 };
   std::ostream_iterator< int > output( cout, " " );
   std::vector< int > v4( a, a + 10 ); // copy of a
   std::vector< int > c2( 10, 0 ); // instantiate vector c2
   cout << "Vector v4 before removing all elements"
      << "\ngreater than 9 and copying:\n   ";
   std::copy( v4.begin(), v4.end(), output );
   std::remove_copy_if( v4.begin(), v4.end(), c2.begin(), greater9 );
   cout << "\nVector c2 after removing all elements"
      << "\ngreater than 9 from v4:\n   ";
   std::copy( c2.begin(), c2.end(), output );
   cout << endl;
   return 0;
}
bool greater9( int x )
{
   return x > 9;
}
 /* 
Vector v4 before removing all elements
greater than 9 and copying:
   10 2 10 4 16 6 14 8 12 10
Vector c2 after removing all elements
greater than 9 from v4:
   2 4 6 8 0 0 0 0 0 0
 */


Use remove_copy_if to copy all elements greater than 3 into a multiset

 
 
   
/* 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 <vector>
#include <deque>
#include <list>
#include <set>
#include <map>
#include <string>
#include <algorithm>
#include <iterator>
#include <functional>
#include <numeric>
/* 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;
}
/* INSERT_ELEMENTS (collection, first, last)
 * - fill values from first to last into the collection
 * - NOTE: NO half-open range
 */
template <class T>
inline void INSERT_ELEMENTS (T& coll, int first, int last)
{
    for (int i=first; i<=last; ++i) {
        coll.insert(coll.end(),i);
    }
}
using namespace std;
int main()
{
    list<int> coll1;
    INSERT_ELEMENTS(coll1,1,6);
    INSERT_ELEMENTS(coll1,1,9);
    PRINT_ELEMENTS(coll1);
    // copy all elements greater than 3 into a multiset
    multiset<int> coll2;
    remove_copy_if(coll1.begin(), coll1.end(),    // source
                   inserter(coll2,coll2.end()),   // destination
                   bind2nd(less<int>(),4));       // elements not copied
    PRINT_ELEMENTS(coll2);
}
 /* 
1 2 3 4 5 6 1 2 3 4 5 6 7 8 9
4 4 5 5 6 6 7 8 9
 */


Use remove_copy_if to print elements without those having a value greater than 4

 
 
    
/* 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 <vector>
#include <deque>
#include <list>
#include <set>
#include <map>
#include <string>
#include <algorithm>
#include <iterator>
#include <functional>
#include <numeric>
/* 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;
}
/* INSERT_ELEMENTS (collection, first, last)
 * - fill values from first to last into the collection
 * - NOTE: NO half-open range
 */
template <class T>
inline void INSERT_ELEMENTS (T& coll, int first, int last)
{
    for (int i=first; i<=last; ++i) {
        coll.insert(coll.end(),i);
    }
}
using namespace std;
int main()
{
    list<int> coll1;
    INSERT_ELEMENTS(coll1,1,6);
    INSERT_ELEMENTS(coll1,1,9);
    PRINT_ELEMENTS(coll1);
    // print elements without those having a value greater than 4
    remove_copy_if(coll1.begin(), coll1.end(),      // source
                   ostream_iterator<int>(cout," "), // destination
                   bind2nd(greater<int>(),4));      // removed elements
    cout << endl;
}
 /* 
1 2 3 4 5 6 1 2 3 4 5 6 7 8 9
1 2 3 4 1 2 3 4
 */
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