Класс "Множество символов"

#include <string>
#include <iostream>
 
class SetOfChar {
 public:
  SetOfChar() {
    clear();
  }
  SetOfChar(const SetOfChar &other) {
    copyFrom(other);
  }
  SetOfChar &operator=(const SetOfChar &other) {
    if (&other != this)
      copyFrom(other);
    return *this;
  }
  SetOfChar &operator<<(unsigned char value) {
    data_[value / 8] |= 1 << (value % 8);
    return *this;
  }
  SetOfChar &operator>>(unsigned char value) {
    data_[value / 8] &= ~(1 << (value % 8));
    return *this;
  }
  bool operator[](unsigned char value) const {
    return has(value);
  }
  SetOfChar operator&(const SetOfChar &other) {
    return intercectionWith(other);
  }
  SetOfChar operator|(const SetOfChar &other) {
    return unionWith(other);
  }
  bool operator<(const SetOfChar &other) {
    return isSubsetOf(other);
  }
  bool operator>(const SetOfChar &other) {
    return other.isSubsetOf(*this);
  }
  SetOfChar intercectionWith(const SetOfChar &other) const {
    SetOfChar result;
    for (unsigned char i = 0; i < 32; ++i)
      result.data_[i] = data_[i] & other.data_[i];
    return result;
  }
  SetOfChar unionWith(const SetOfChar &other) const {
    SetOfChar result;
    for (unsigned char i = 0; i < 32; ++i)
      result.data_[i] = data_[i] | other.data_[i];
    return result;
  }
  bool isSubsetOf(const SetOfChar &other) const {
    for (unsigned char i = 0; i < 32; ++i)
      if (((data_[i] & other.data_[i]) ^ data_[i]) != 0)
        return false;
    return true;
  }
  bool operator==(const SetOfChar &other) const {
    return equalsTo(other);
  }
  bool equalsTo(const SetOfChar &other) const {
    for (unsigned char i = 0; i < 32; ++i)
      if (data_[i] != other.data_[i])
        return false;
    return true;
  }
  bool has(unsigned char value) const {
    return ((data_[value / 8] & (1 << (value % 8))) != 0);
  }
  bool isEmpty() const {
    for (size_t i = 0; i < 32; ++i)
      if (data_[i] != 0)
        return false;
    return true;
  }
  void clear() {
    for (size_t i = 0; i < 32; ++i)
      data_[i] = 0;
  }
  void copyFrom(const SetOfChar &other) {
    for (size_t i = 0; i < 32; ++i)
      data_[i] = other.data_[i];
  }
 private:
  unsigned char data_[32];
};
 
std::ostream &operator<<(std::ostream &stream, const SetOfChar &set) {
  for (unsigned char i = 0; i < 255; ++i)
    if (set[i])
      stream << static_cast<int>(i) << " ";
  return stream;
}
 
int main(int argc, char *argv[]) {
  SetOfChar a, b, c;
  a << 1 << 2 << 4 << 6;
  b << 2 << 3 << 5 << 6;
  c = (a | b);
 
  std::cout << "a: " << a << std::endl << "b: " << b << std::endl <<
    "c: " << c << std::endl;
  std::cout << "Union: " << (a | b) << std::endl;
  std::cout << "Intersection: " << (a & b) << std::endl;
  std::cout << "C includes A: " << ((c > a) ? "yes" : "no") << std::endl;
  std::cout << "C includes B: " << ((c > b) ? "yes" : "no") << std::endl;
  std::cout << "A includes B: " << ((a > b) ? "yes" : "no") << std::endl;
  std::cout << "A equals to B: " << ((a == b) ? "yes" : "no") << std::endl;
  return 0;
}