C++位集实现与高效状态管理技巧

#include <bitset>
#include <iostream>
int main() {
std::bitset<8> flags;         // 8位位集
flags.set(0);                 // 设置第0位为1
flags.set(2);
std::cout << flags << "\n";   // 输出: 00000101
if (flags.test(0)) {
    std::cout &lt;&lt; "第0位已设置\n";
}

flags.flip();                 // 翻转所有位
std::cout &lt;&lt; flags &lt;&lt; "\n";   // 输出: 11111010
}

class DynamicBitset {
private:
    std::vector<uint64_t> data;
    size_t n_bits;
static constexpr int WORD_SIZE = 64;
public:
explicit DynamicBitset(size_t bits) : n_bits(bits) {
data.resize((bits + WORD_SIZE - 1) / WORD_SIZE, 0);
}
void set(size_t pos) {
    if (pos &gt;= n_bits) return;
    data[pos / WORD_SIZE] |= (1ULL &lt;&lt; (pos % WORD_SIZE));
}

void reset(size_t pos) {
    if (pos &gt;= n_bits) return;
    data[pos / WORD_SIZE] &amp;= ~(1ULL &lt;&lt; (pos % WORD_SIZE));
}

bool test(size_t pos) const {
    if (pos &gt;= n_bits) return false;
    return (data[pos / WORD_SIZE] &gt;&gt; (pos % WORD_SIZE)) &amp; 1;
}
};

int popcount(uint64_t x) {
    int cnt = 0;
    while (x) {
        x &= x - 1;  // 每次清除最低位的1
        cnt++;
    }
    return cnt;
}