Standard C++ LibraryCopyright 1996, Rogue Wave Software, Inc.

NAME

  remove_copy_if  - Move desired elements to the front of a container, and
  return an iterator that describes where the sequence of desired elements
  ends.

SYNOPSIS

  #include <algorithm>

  template <class InputIterator,
           class OutputIterator,
           class Predicate>
  OutputIterator remove_copy_if (InputIterator first,
                                 InputIterator last,
                                 OutputIterator result,
                                 Predicate pred);

DESCRIPTION

  The remove_copy_if algorithm copies all the elements referred to by the
  iterator i in the range [first, last) for which the following condition
  does not hold:  pred(*i)  == true. remove_copy_if returns the end of the
  resulting range.  remove_copy_if is stable, that is, the relative order of
  the elements in the resulting range is the same as their relative order in
  the original range.

COMPLEXITY

  Exactly last1 - first1 applications of the corresponding predicate are
  done.

EXAMPLE

  //
  // remove.cpp
  //
   #include <algorithm>
   #include <vector>
   #include <iterator>
   #include <iostream.h>

  template<class Arg>
  struct all_true : public unary_function<Arg, bool>
   {
    bool operator() (const Arg&) { return 1; }
   };

  int main ()
   {
    int arr[10] = {1,2,3,4,5,6,7,8,9,10};
    vector<int> v(arr+0, arr+10);

    copy(v.begin(),v.end(),ostream_iterator<int,char>(cout," "));
    cout << endl << endl;
     //
     // Remove the 7.
     //
    vector<int>::iterator result = remove(v.begin(), v.end(), 7);
     //
     // Delete dangling elements from the vector.
     //
    v.erase(result, v.end());

    copy(v.begin(),v.end(),ostream_iterator<int,char>(cout," "));
    cout << endl << endl;
     //
     // Remove everything beyond the fourth element.
     //
    result = remove_if(v.begin()+4, v.begin()+8, all_true<int>());
     //
     // Delete dangling elements.
     //
    v.erase(result, v.end());

    copy(v.begin(),v.end(),ostream_iterator<int,char>(cout," "));
    cout << endl << endl;
     //
     // Now remove all 3s on output.
     //
    remove_copy(v.begin(), v.end(),
                   ostream_iterator<int>(cout," "), 3);
    cout << endl << endl;
     //
     // Now remove everything satisfying predicate on output.
     // Should yield a NULL vector.
     //
     remove_copy_if(v.begin(), v.end(),
                       ostream_iterator<int,char>(cout," "),
                   all_true<int>());

    return 0;
   }
  Output :
  1 2 3 4 5 6 7 8 9 10
  1 2 3 4 5 6 8 9 10
  1 2 3 4
  1 2 4

WARNING

  If your compiler does not support default template parameters, then you
  need to always supply the Allocator template argument.  For instance, you
  will need to write :

  vector<int, allocator<int> >

  instead of :

  vector<int>

SEE ALSO

  remove, remove_if, remove_copy

STANDARDS CONFORMANCE

  ANSI X3J16/ISO WG21 Joint C++ Committee



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