C++ Error: 'bit_vector' Incomplete Type, Subscript Operator, and 'empty' Member

To fix the errors in the provided code, you need to define the 'bit_vector' class and include any necessary headers. Additionally, you need to ensure that the 'bit_vector' class provides a subscript operator and a member function called 'empty'.

Here's an example of how you can define the 'bit_vector' class with a subscript operator and 'empty' member function:

class bit_vector {
public:
    // Define the subscript operator
    bool& operator[](size_t index) {
        return bits[index];
    }

    // Define the empty member function
    bool empty() const {
        return bits.empty();
    }

    // Define the resize member function
    void resize(size_t count) {
        bits.resize(count);
    }

private:
    std::vector<bool> bits; // Use std::vector<bool> to store the bits
};

Make sure to include the necessary headers at the top of your code:

#include <vector>

With these changes, the code should compile without errors.