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                       Standard C++ Library
             Copyright 1998, Rogue Wave Software, Inc.


NAME
     remove_copy_if

      - Moves desired elements to the front of a  container,  and
     returns  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 an iterator that points to the
     end of the resulting range. remove_copy_if is stable,  which
     means that the relative order of the elements in the result-
     ing range is the same as their relative order in the  origi-
     nal range.



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



EXAMPLE
     //
     // remove.cpp
     //
      #include <algorithm>
      #include <vector>
      #include <iterator>
      #include <iostream>
     using namespace std;

     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(),            <br>
       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(),          <br>
        ostream_iterator<int,char>(cout," "),
                      all_true<int>());

       return 0;
      }

     Program 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



WARNINGS
     If your compiler does not support default  template  parame-
     ters,  then you always need to supply the Allocator template
     argument. For instance, you need to write:

     vector<int, allocator<int> >

     instead of:

     vector<int>

     If your compiler does not support namespaces,  then  you  do
     not need the using declaration for std.



SEE ALSO
     remove, remove_if, remove_copy

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