bitset::count

返回在位顺序设置的位数。

size_t count( ) const;

返回值

在位顺序设置的位数。

示例

当编译此示例与 /Wp64 标记或在64位平台时，警告的编译器C4267将生成。有关此警告的更多信息，请参见 编译器警告（等级 3）C4267。

// bitset_count.cpp
// compile with: /EHsc
#include <bitset>
#include <iostream>

int main( )
{
    using namespace std;

    bitset<5> b1(4);

    cout << "The collection of bits in the original bitset is: ( "
         << b1 << " )" << endl;

    size_t i;
    i = b1.count();
    cout << "The number of bits in the bitset set to 1 is: "
         << i << "." << endl;

    bitset<5> fb1;
    fb1 = b1.flip();

    cout << "The collection of flipped bits in the modified bitset "
         << "is: ( " << b1 << " )" << endl;

    size_t ii;
    ii = fb1.count();
    cout << "The number of bits in the bitset set to 1 is: "
         << ii << "." << endl;
}

要求

标头: <bitset>

命名空间: std

请参见

参考

bitset Class