STL_Bitset-蒲公英云

1.构造

<span style="font-family:Microsoft YaHei;font-size:24px;">std::bitset<16> foo;//构造16位的无参默认为0的位图
    std::bitset<16> bar(0xfa2);//转化为二进制形式
    std::bitset<16> baz(std::string("0101111001"));
    std::cout << "foo: " << foo << '\n';
    std::cout << "bar: " << bar << '\n';
    std::cout << "baz: " << baz << '\n';</span>

Center

bitset::operator[]:

<span style="font-family:Microsoft YaHei;font-size:24px;">// bitset::operator[]
#include <iostream>       // std::cout
#include <bitset>         // std::bitset
int main()
{
    std::bitset<4> foo;
    foo[1] = 1;             // 0010
    foo[2] = foo[1];        // 0110
    //operator[] 设置位图的具体位置的数字
    std::cout << "foo: " << foo << '\n';
    system("pause");
    return 0;
}</span>

bitset::count() :计算已经被设置的个数（1的个数）

<span style="font-family:Microsoft YaHei;font-size:24px;">// bitset::count
#include <iostream>       // std::cout
#include <string>         // std::string
#include <bitset>         // std::bitset
int main()
{
    std::bitset<8> foo(std::string("10110011"));
    std::cout << foo << " has ";
    std::cout << foo.count() << " ones and ";
    std::cout << (foo.size() - foo.count()) << " zeros.\n";
    system("pause");
    return 0;
}</span>

bitset::size(): 求出bitset的大小

bitset::test(): 可以判断某一位是否为1，若为1，返回true，若为0，返回false

bitset::set():设置

<span style="font-family:Microsoft YaHei;font-size:24px;">// bitset::set
#include <iostream>       // std::cout
#include <bitset>         // std::bitset
int main()
{
    std::bitset<4> foo;
    std::cout << foo.set() << '\n';     //设置全为1
    std::cout << foo.set(2, 0) << '\n'; //下标为2的设置为0
    std::cout << foo.set(2) << '\n';    //设置下标2（从右开始数），默认为1
    system("pause");
    return 0;
}</span>

Center 1

bitset::reset():设置为0

<span style="font-family:Microsoft YaHei;font-size:24px;">std::bitset<4> foo(std::string("1011"));
    //reset():设置为0
    std::cout << foo.reset(1) << '\n';//原来是1，设置后变为0
    std::cout << foo.reset() << '\n'; //全部变为0</span>

bitset::flip():

<span style="font-family:Microsoft YaHei;font-size:24px;">// bitset::flip
#include <iostream>       // std::cout
#include <string>         // std::string
#include <bitset>         // std::bitset
int main()
{
    std::bitset<4> foo(std::string("0001"));
    std::cout << foo.flip(2) << '\n';// 0101 ,将下标为2的数字翻转为1
    std::cout << foo.flip() << '\n';// 1010，将foo全部翻转
    system("pause");
    return 0;
}</span>