std::hash (std::bitset)

 

C++

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std::bitset

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bitset::bitset

bitset::operator== bitset::operator!=

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bitset::all bitset::any bitset::none (C++11)

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bitset::operator&= bitset::operator|= bitset::operator^= bitset::operator~

bitset::operator<<= bitset::operator>>= bitset::operator<< bitset::operator>>

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bitset::to_string

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bitset::to_ullong (C++11)

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operator& operator| operator^

operator<< operator>>

Helper classes

std::hash (C++11)

 

template<size_t N> struct hash<bitset<N>>;		(since C++11)

The template specialization of std::hash for std::bitset<N> allows users to obtain hashes of objects of type std::bitset<N>.

Example

The following code shows one possible output of a hash function used on several bitsets:

run this code

#include <iostream>
#include <bitset>
#include <functional>
 
int main()
{
    std::bitset<4> b1(1);
    std::bitset<4> b2(2);
    std::bitset<4> b3(b2);
 
    std::hash<std::bitset<4>> hash_fn;
 
    size_t h1 = hash_fn(b1);
    size_t h2 = hash_fn(b2);
    size_t h3 = hash_fn(b3);
 
    std::cout << h1 << '\n';
    std::cout << h2 << '\n';
    std::cout << h3 << '\n';
}

Output:

67918732
118251589
118251589

See also

hash (C++11)	hash function object (class template)