public member function
<unordered_set>

std::unordered_multiset::load_factor

float load_factor() const noexcept;
Return load factor
Returns the current load factor in the unordered_multiset container.

The load factor is the ratio between the number of elements in the container (its size) and the number of buckets (bucket_count):

load_factor = size / bucket_count

The load factor influences the probability of collision in the hash table (i.e., the probability of two elements being located in the same bucket). The container automatically increases the number of buckets to keep the load factor below a specific threshold (its max_load_factor), causing a rehash each time an expansion is needed.

To retrieve or change this threshold, use member function max_load_factor.

Parameters

none

Return Value

The current load factor.

Example

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// unordered_multiset hash table stats
#include <iostream>
#include <unordered_set>

int main ()
{
  std::unordered_multiset<int> myums;

  std::cout << "size = " << myums.size() << std::endl;
  std::cout << "bucket_count = " << myums.bucket_count() << std::endl;
  std::cout << "load_factor = " << myums.load_factor() << std::endl;
  std::cout << "max_load_factor = " << myums.max_load_factor() << std::endl;

  return 0;
}


Possible output:
size = 0
bucket_count = 11
load_factor = 0
max_load_factor = 1

Complexity

Constant.

Iterator validity

No changes.

See also

  • 9316991614 2018-02-25
  • 191841613 2018-02-25
  • 16411612 2018-02-25
  • 6081981611 2018-02-25
  • 1784561610 2018-02-25
  • 4651609 2018-02-25
  • 9348111608 2018-02-25
  • 2513771607 2018-02-25
  • 6478461606 2018-02-24
  • 4985791605 2018-02-24
  • 5637141604 2018-02-24
  • 282181603 2018-02-24
  • 6217941602 2018-02-24
  • 5076141601 2018-02-24
  • 714281600 2018-02-24
  • 6607141599 2018-02-24
  • 949041598 2018-02-24
  • 6809961597 2018-02-24
  • 671871596 2018-02-24
  • 7107821595 2018-02-24