function template

std::replace_copy

<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 );
Copy range replacing value
Copies the values of the elements in the range [first,last) to the range positions beginning at result, replacing the appearances of old_value by new_value.

The behavior of this function template is equivalent to:
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template < class InputIterator, class OutputIterator, class T >
  OutputIterator replace_copy ( InputIterator first, InputIterator last,
                                OutputIterator result, const T& old_value, const T& new_value )
{
  for (; first != last; ++first, ++result)
    *result = (*first==old_value)? new_value: *first;
  return result;
}


Parameters

first, last
Input iterators to the initial and final positions in a sequence. The range used is [first,last), which contains all the elements between first and last, including the element pointed by first but not the element pointed by last.
result
Output iterator to the initial position of the range where the function's results are stored. The range includes as many elements as [first,last).
old_value
Value to be replaced.
new_value
Replacement value.

Return value

An iterator pointing to the element that follows the last element written in the result sequence.

Example

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// replace_copy example
#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;

int main () {
  int myints[] = { 10, 20, 30, 30, 20, 10, 10, 20 };

  vector<int> myvector (8);
  replace_copy (myints, myints+8, myvector.begin(), 20, 99);

  cout << "myvector contains:";
  for (vector<int>::iterator it=myvector.begin(); it!=myvector.end(); ++it)
    cout << " " << *it;

  cout << endl;
 
  return 0;
}


Output:
myvector contains: 10 99 30 30 99 10 10 99

Complexity

Performs as many comparisons and assignments as the number of elements in the range [first,last).

See also