C++ Bitset Library - hash() Function

Description

The C++ function std::bitset::hash() returns hash value based on the provided bitset. It always returns same hash value for same bitset.

Declaration

Following is the declaration for std::bitset::hash() function form std::bitset header.

C++11

template <class T> struct hash;
template <size_t N> struct hash<bitset<N>>;

Return value

Calculates and returns a hash value based on bitset.

Example

#include <iostream>
#include <bitset>

using namespace std;

int main(void) {

   bitset<4> b1(1);
   bitset<4> b2(4);

   std::hash<std::bitset<4>> hash_fun;

   cout << "Hash function for b1 = " << hash_fun(b1) << endl;
   cout << "Hash function for b2 = " << hash_fun(b2) << endl;

   return 0;
}

Let us compile and run the above program, this will produce the following result −

Hash function for b1 = 4334672815104069193
Hash function for b2 = 4228082005917330485