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

NAME

  replace_copy_if  - Substitutes elements stored in a collection with new
  values.

SYNOPSIS

  #include <algorithm>
  template <class InputIterator,
           class OutputIterator,
           class Predicate,
           class T>
  OutputIterator replace_copy_if (InputIterator first,
                                 InputIterator last,
                                 OutputIterator result,
                                 Predicate pred,
                                 const T& new_value);

DESCRIPTION

  The replace_copy_if algorithm leaves the original sequence intact and
  places a revised sequence into result.  The algorithm compares each element
  *i in the range [first,last) with the conditions specified by pred.   If
  pred(*i)==false, replace_copy_if copies *i to result+(first-i).  If
  pred(*i)==true, then replace_copy copies new_value to result+(first-i).
  replace_copy_if returns result+(last-first).

COMPLEXITY

  Exactly last - first applications of the predicate are performed.

EXAMPLE

  //
  // replace.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 ()
   {
     //
     // 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(),
                        ostream_iterator<int,char>(cout, " "),
                    all_true<int>(), 19);
    cout << endl;

    return 0;
   }
  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

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

  replace, replace_if, replace_copy

STANDARDS CONFORMANCE

  ANSI X3J16/ISO WG21 Joint C++ Committee



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