remove


function template
<algorithm>
template < class ForwardIterator, class T >
  ForwardIterator remove ( ForwardIterator first, ForwardIterator last,
                           const T& value );

Remove value from range

Removes from the range [first,last) the elements with a value equal to value and returns an iterator to the new end of the range, which now includes only the values not equal to value.

The behavior of this function template is equivalent to:
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template < class ForwardIterator, class T >
  ForwardIterator remove ( ForwardIterator first, ForwardIterator last, const T& value )
{
  ForwardIterator result = first;
  for ( ; first != last; ++first)
    if (!(*first == value)) *result++ = *first;
  return result;
}


Notice that this function does not alter the elements past the new end, which keep their old values and are still accessible.

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.
value
Value to be removed.


Return value

A forward iterator pointing to the new end of the sequence, which now includes all the elements with a value other than value.

Example

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

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

  // bounds of range:
  int* pbegin = myints;                          // ^
  int* pend = myints+sizeof(myints)/sizeof(int); // ^                       ^

  pend = remove (pbegin, pend, 20);              // 10 30 30 10 10 10 10 20
                                                 // ^              ^
  cout << "range contains:";
  for (int* p=pbegin; p!=pend; ++p)
    cout << " " << *p;

  cout << endl;
 
  return 0;
}


Output:
range contains: 10 30 30 10 10


Complexity

Performs as many comparisons as the number of elements in the range [first,last), and at most as many assignment operations.

See also

remove_if Remove elements from range (function template)
remove_copy Copy range removing value (function template)
replace Replace value in range (function template)
count Count appearances of value in range (function template)
find Find value in range (function template)