Password Generator | C++

// author - aws (nt_qwark)

#include <iostream>
#include <sstream>

struct PasswordGenerateSettings
{
public:
    bool UseUpper = true;
    bool UseDigits = true;
    bool OnlyUpper = false;
    bool OnlyDigits = false;
    char DelemiterSymbol = '-';
    unsigned SectionsCount = 4;
    unsigned SymbolsInSection = 5;
};

std::string GeneratePassword(PasswordGenerateSettings& settings)
{
    std::stringstream buffer;

    for (size_t i = 0; i < static_cast<size_t>(settings.SectionsCount * settings.SymbolsInSection); i++)
    {
        char randChar = rand() % 25 + 'a';
        bool isUpper = rand() % 2;
        bool isDigit = rand() % 2;

        isUpper = isUpper || settings.OnlyUpper;
        isDigit = isDigit || settings.OnlyDigits;

        if (settings.UseUpper && isUpper)
            randChar = toupper(randChar);

        if (isDigit)
            randChar = rand() % 10 + '0';

        if (i % settings.SymbolsInSection == 0 && i != 0)
            buffer << settings.DelemiterSymbol;

        buffer << randChar;
    }

    return buffer.str();
}

// generate pass with default settings
std::string GeneratePassword()
{
    PasswordGenerateSettings defaultSettings;
    return GeneratePassword(defaultSettings);
}

int main()
{
    srand(clock());

    while (true)
    std::cout << GeneratePassword() << std::endl;

    return (0);
}

// example output:
// 40J6o-7J0o1-981e0-r54dE
// 1Yn96-x6b4e-4m574-570xE
// etc