replace_copy (STL Samples)
Illustrates how to use the replace_copy Standard Template Library (STL) function in Visual C++.
template<class ForwardIterator, class OutputIterator, class Type> inline
OutputIterator replace_copy(
ForwardIterator First,
ForwardIterator Last,
OutputIterator Result,
const T& Old_Value,
const T& New_Value
)
Remarks
Note
The class/parameter names in the prototype do not match the version in the header file. Some have been modified to improve readability.
The replace_copy algorithm copies all elements from the range [First, Last) to a same-size range starting at result, replacing all occurrences of Old_Value with New_Value in the resulting sequence. It returns an iterator positioned immediately after the last new element in the resulting sequence.
Example
// replace_copy.cpp
// compile with: /EHsc
// Illustrates how to use the replace_copy function.
//
// Functions:
// replace_copy - Copy the elements of a sequence to another
// same-size sequence replacing any elements
// that match a value with another value.
// disable warning C4786: symbol greater than 255 characters,
// okay to ignore
#pragma warning(disable: 4786)
#include <iostream>
#include <vector>
#include <algorithm>
#include <functional>
using namespace std;
int main()
{
const int MAX_ELEMENTS = 8 ;
// Define a template class vector of integers
typedef vector<int > IntVector ;
//Define an iterator for template class vector of integer
typedef IntVector::iterator IntVectorIt ;
//vector containing numbers
IntVector Numbers(MAX_ELEMENTS), Result(MAX_ELEMENTS) ;
IntVectorIt start, end, it, last, resultIt ;
//Initialize vector Numbers
Numbers[0] = 10 ;
Numbers[1] = 20 ;
Numbers[2] = 10 ;
Numbers[3] = 15 ;
Numbers[4] = 12 ;
Numbers[5] = 7 ;
Numbers[6] = 9 ;
Numbers[7] = 10 ;
start = Numbers.begin() ; // location of first
// element of Numbers
end = Numbers.end() ; // one past the location
// last element of Numbers
resultIt = Result.begin() ; // location of first
// element of Result
// print content of Numbers
cout << "Numbers { " ;
for(it = start; it != end; it++)
cout << *it << " " ;
cout << " }\n" << endl ;
// copy all elements from Numbers to Result
// replacing any item that equals 10 with 30
last = replace_copy(start, end, resultIt, 10, 30) ;
//print number of elements copied to Result
cout << "Total number of elements copied to Result = "
<< last - resultIt << endl ;
start = Result.begin() ; // location of first
// element of Result
end = Result.end() ; // one past the location
// last element of Result
// print content of Result
cout << "Result { " ;
for(it = start; it != end; it++)
cout << *it << " " ;
cout << " }\n" << endl ;
}
Output
Numbers { 10 20 10 15 12 7 9 10 }
Total number of elements copied to Result = 8
Result { 30 20 30 15 12 7 9 30 }
Requirements
Header: <algorithm>