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      std::inplace_vector<T,N>::erase

      From cppreference.com
      <cpp‎ |container‎ |inplace vector

      [edit template]
       
       
       
      std::inplace_vector
      Member types
      Member functions
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      constexpr iterator erase( const_iterator pos);
      (1)(since C++26)
      constexpr iterator erase( const_iterator first, const_iterator last);
      (2)(since C++26)

      Erases the specified elements from the container.

      1) Removes the element atpos.
      2) Removes the elements in the range[firstlast).

      Iterators (including theend() iterator) and references to the elements at or after the point of the erase are invalidated.

      The iteratorpos must be valid and dereferenceable. Thus theend() iterator (which is valid, but is not dereferenceable) cannot be used as a value forpos.

      The iteratorfirst does not need to be dereferenceable iffirst== last: erasing an empty range is a no-op.

      Contents

      [edit]Parameters

      pos - iterator to the element to remove
      first, last - the pair of iterators defining therange of elements to remove
      Type requirements
      -
      IfT is notMoveAssignable, the behavior is undefined.

      [edit]Return value

      Iterator following the last removed element.

      1) Ifpos refers to the last element, then theend() iterator is returned.
      2) Iflast== end() prior to removal, then the updatedend() iterator is returned.
      If[firstlast) is an empty range, thenlast is returned.

      Exceptions

      Does not throw unless an exception is thrown by the assignment operator ofT.

      [edit]Complexity

      Linear: the number of calls to the destructor ofT is the same as the number of elements erased, the assignment operator ofT is called the number of times equal to the number of elements in the vector after the erased elements.

      [edit]Notes

      When container elements need to be erased based on a predicate, rather than iterating the container and calling unaryerase, the iterator range overload is generally used withstd::remove()/std::remove_if() to minimise the number of moves of the remaining (non-removed) elements, — this is the erase-remove idiom.std::erase_if() replaces the erase-remove idiom.

      [edit]Example

      Run this code
      #include <inplace_vector>#include <print> int main(){std::inplace_vector<int,10> v{0,1,2,3,4,5,6,7,8,9};std::println("{}", v);     v.erase(v.begin());std::println("{}", v);     v.erase(v.begin()+2, v.begin()+5);std::println("{}", v); // Erase all even numbersfor(std::inplace_vector<int,10>::iterator it{v.begin()}; it!= v.end();)if(*it%2==0)            it= v.erase(it);else++it;std::println("{}", v);}

      Output:

      [0, 1, 2, 3, 4, 5, 6, 7, 8, 9][1, 2, 3, 4, 5, 6, 7, 8, 9][1, 2, 6, 7, 8, 9][1, 7, 9]

      [edit]See also

      erases all elements satisfying specific criteria
      (function template)[edit]
      clears the contents
      (public member function)[edit]
      Retrieved from "https://en.cppreference.com/mwiki/index.php?title=cpp/container/inplace_vector/erase&oldid=175278"

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