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<P>©Copyright 1996 Rogue Wave Software</P>
<H2>remove_copy_if</H2>
<HR><PRE> Algorithm</PRE><HR>
<A NAME="Summary"><H3>Summary</H3></A>
<P>Move desired elements to the front of a container, and return an iterator that describes where the sequence of desired elements ends.</P>
<H3>Contents</H3>
<UL>
<A HREF="#Synopsis"><LI>Synopsis</LI></A>
<A HREF="#Description"><LI>Description</LI></A>
<A HREF="#Complexity"><LI>Complexity</LI></A>
<A HREF="#Example"><LI>Example</LI></A>
<A HREF="#Warning"><LI>Warning</LI></A>
<A HREF="#See Also"><LI>See Also</LI></A>
</UL>
<A NAME="Synopsis"><H3>Synopsis</H3></A>
<PRE>#include <algorithm></PRE>
<PRE>
template <class InputIterator,
class OutputIterator,
class Predicate>
OutputIterator <B>remove_copy_if</B> (InputIterator first,
InputIterator last,
OutputIterator result,
Predicate pred);
</PRE>
<A NAME="Description"><H3>Description</H3></A>
<P>The <B><I>remove_copy_if</B></I> algorithm copies all the elements referred to by the iterator <SAMP>i</SAMP> in the range <SAMP>[first, last)</SAMP> for which the following condition does <I>not</I> hold: <SAMP>pred(*i) == true</SAMP>. <B><I>remove_copy_if</B></I> returns the end of the resulting range. <B><I>remove_copy_if</B></I> 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. </P>
<A NAME="Complexity"><H3>Complexity</H3></A>
<P>Exactly <SAMP>last1 - first1 </SAMP>applications of the corresponding predicate are done. </P>
<A NAME="Example"><H3>Example</H3></A>
<PRE>//
// 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>(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>(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>(cout," "));
cout << endl << endl;
//
<B> </B>// Now remove all 3s on output.
//
remove_copy(v.begin(), v.end(), ostream_iterator<int>(cout," "), 3);</PRE>
<PRE> cout << endl << endl;
//
<B> </B>// Now remove everything satisfying predicate on output.
// Should yield a NULL vector.
//
<B>remove_copy_if</B>(v.begin(), v.end(), ostream_iterator<int>(cout," "),</PRE>
<PRE> all_true<int>());
return 0;
}</PRE><PRE>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</PRE>
<A NAME="Warning"><H3>Warning</H3></A>
<P>If your compiler does not support default template parameters, then you need to always supply the <SAMP>Allocator</SAMP> template argument. For instance, you will need to write :</P>
<P><SAMP>vector<int, allocator></SAMP></P>
<P>instead of :</P>
<P><SAMP>vector<int></SAMP></P>
<A NAME="See Also"><H3>See Also</H3></A>
<P><A HREF="rem_4572.htm"><B><I>remove</B></I></A>, <A HREF="rem_0514.htm"><B><I>remove_if</B></I></A>, <A HREF="rem_6253.htm"><B><I>remove_copy</B></I></A></P>
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