def convert_temp(temp, input_scale="celsius", output_scale="celsius"):
    scales = {
        "celsius": (1, 0),
        "kelvin": (1, 273.15),
        "fahrenheit": (1.8, 32)
    }

    factor_in, offset_in = scales.get(input_scale, (1, 0))
    factor_out, offset_out = scales.get(output_scale, (1, 0))

    temp_celsius = (temp - offset_in) / factor_in

    result = (temp_celsius * factor_out) + offset_out

    return result
end