public member function
<forward_list>

std::forward_list::max_size

size_type max_size () const noexcept;
Return maximum size
Returns the maximum number of elements that the forward_list container can hold.

This is the maximum potential number of elements the container can reach due to known system or library implementation limitations, but the container is by no means guaranteed to be able to reach that size: it can still fail to allocate storage at any point before that size is reached.

Parameters

none

Return Value

The maximum number of elements the object can hold as content.

Member type size_type is an unsigned integral type.

Example

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// forward_list::max_size
#include <iostream>
#include <sstream>
#include <forward_list>

int main ()
{
  int myint;
  std::string mystring;
  std::forward_list<int> mylist;

  std::cout << "Enter size: ";
  std::getline ( std::cin, mystring );
  std::stringstream ( mystring ) >> myint;

  if ( myint <= mylist.max_size() ) mylist.resize(myint);
  else std::cout << "That size exceeds the maximum.\n";

  return 0;
}

Here, member max_size is used to check beforehand whether the requested size will be allowed by member resize.

Complexity

Constant.

Iterator validity

No changes.

Data races

The container is accessed.
No contained elements are accessed: concurrently accessing or modifying them is safe.

Exception safety

No-throw guarantee: this member function never throws exceptions.

See also