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


NAME
     replace_copy

      - Substitutes elements in a collection with new values, and
     moves the revised sequence into result.



SYNOPSIS
     #include <algorithm>
     template <class InputIterator,
              class OutputIterator,
              class T>
     OutputIterator replace_copy (InputIterator first,
                                 InputIterator last,
                                 OutputIterator result,
                                 const T& old_value,
                                 const T& new_value);



DESCRIPTION
     The replace_copy  algorithm  leaves  the  original  sequence
     intact  and places the revised sequence into result. For the
     range  [first,  last),  the  algorithm   compares   elements
     referred  to  by  iterator  i with old_value. If *i does not
     equal   old_value,   then   replace_copy   copies   *i    to
     result+(first-i). If *i==old_value, then replace_copy copies
     new_value   to   result+(first-i).   replace_copy    returns
     result+(last-first).



COMPLEXITY
     Exactly last - first comparisons between values are done.



EXAMPLE
     //
     // replace.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 ()
      {
        //
        // Initialize a vector with an array of integers.
        //
       int arr[10] = {1,2,3,4,5,6,7,8,9,10};
       vector<int> v(arr+0, arr+10);
        //
        // Print out original vector.
        //
       cout << "The original list: "<< endl << "     ";
       copy(v.begin(), v.end(),
            ostream_iterator<int,char>(cout," "));
       cout << endl << endl;
        //
        // Replace the number 7 with 11.
        //
       replace(v.begin(), v.end(), 7, 11);
        //
        // Print out vector with 7 replaced.
        //
       cout << "List after replace:" << endl << "     ";
       copy(v.begin(), v.end(),
            ostream_iterator<int,char>(cout," "));
       cout << endl << endl;
        //
        // Replace 1 2 3 with 13 13 13.
        //
       replace_if(v.begin(), v.begin()+3, all_true<int>(), 13);
        //
        // Print out the remaining vector.
        //
       cout << "List after replace_if:" << endl << "     ";
       copy(v.begin(), v.end(),
            ostream_iterator<int,char>(cout," "));
       cout << endl << endl;
        //
        // Replace those 13s with 17s on output.
        //
       cout << "List using replace_copy to cout:" << endl
             << "     ";

        replace_copy(v.begin(), v.end(),
                        ostream_iterator<int,char>(cout, " "),
                     13, 17);
       cout << endl << endl;
        //
        // A simple example of replace_copy_if.
        //
       cout << "List w/ all elements output as 19s:" << endl
            << "   ";
       replace_copy_if(v.begin(),          v.end(),          <br>
       ostream_iterator<int,char>(cout, " "),
                       all_true<int>(), 19);
       cout << endl;

       return 0;
      }

     Program Output



     The original list:
         1 2 3 4 5 6 7 8 9 10
     List after replace:
         1 2 3 4 5 6 11 8 9 10
     List after replace_if:
         13 13 13 4 5 6 11 8 9 10
     List using replace_copy to cout:
         17 17 17 4 5 6 11 8 9 10
     List with all elements output as 19s:
         19 19 19 19 19 19 19 19 19 19



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
     replace, replace_if, replace_copy_if

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