C++ Bitset Library - count() Function

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Description

The C++ function std::bitset::count() count number of set bits from bitset.

Declaration

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

C++98

 size_t count() const; 

C++11

 size_t count() const noexcept; 

Parameters

None

Return value

Returns number of set bits.

Exceptions

This member function never throws exception.

Example

The following example shows the usage of std::bitset::count() function.

 #include <iostream> #include <bitset> using namespace std; int main(void) { bitset<4> b("1110"); cout << "In bitset " << b << ", " << b.count() << " bits are set." << endl; return 0; } 

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

 In bitset 1110, 3 bits are set.