Unordered_set: load_factor-C ++ reference

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Unordered_set: load_factor-C ++ reference

Public member function STD :: Unordered_set: load_factor <unordered_set>
 
Float load_factor () const notest;
Return load factor

Returns the current load factor in the unordered_set 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_set hash table stats# Include <iostream># Include <unordered_set>IntMain () {STD: unordered_set <Int> Myset; STD: cout <"Size ="<Myset. Size () <STD: Endl; STD: cout <"Bucket_count ="<Myset. bucket_count () <STD: Endl; STD: cout <"Load_factor ="<Myset. load_factor () <STD: Endl; STD: cout <"Max_load_factor ="<Myset. max_load_factor () <STD: Endl;Return0 ;}

Possible output:

  size = 0bucket_count = 11load_factor = 0max_load_factor = 1  

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