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remove_copy_if
function template
<algorithm>
template <class InputIterator, class OutputIterator, class Predicate>
OutputIterator remove_copy_if ( InputIterator first, InputIterator last,
OutputIterator result, Predicate pred );
Copy range removing values
Copies the values of the elements in the range [first,last) to the range positions beginning at result, except those for which pred is true, which are not copied.
The behavior of this function template is equivalent to:
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template <class InputIterator, class OutputIterator, class Predicate>
OutputIterator remove_copy_if ( InputIterator first, InputIterator last,
OutputIterator result, Predicate pred )
{
for ( ; first != last; ++first)
if (!pred(*first)) *result++ = *first;
return result;
}
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Parameters
- first, last
- Forward 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 resulting range of values is stored.
- pred
- Unary predicate taking an element in the range as argument, and returning a value indicating the falsehood (with false, or a zero value) or truth (true, or non-zero) of some condition applied to it. This can either be a pointer to a function or an object whose class overloads operator().
Return value
An output iterator pointing to the end of the copied range, which includes all the elements in [first,last) except for those for which pred was true.
Example
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// remove_copy_if example
#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;
bool IsOdd (int i) { return ((i%2)==1); }
int main () {
int myints[] = {1,2,3,4,5,6,7,8,9};
vector<int> myvector (9);
vector<int>::iterator it;
remove_copy_if (myints,myints+9,myvector.begin(),IsOdd);
cout << "myvector contains:";
for (it=myvector.begin(); it!=myvector.end(); ++it)
cout << " " << *it;
cout << endl;
return 0;
}
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Output:
myvector contains: 2 4 6 8 0 0 0 0 0
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Complexity
Applies pred as many times as the number of elements in the range [first,last), and at most, that same amount of assignment operations.
See also
| remove | Remove value from range (function template) |
| remove_copy | Copy range removing value (function template) |
| count | Count appearances of value in range (function template) |
| copy | Copy range of elements (function template) |
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