I would expect a novice to manage this task in (much) less than a day.
Well, your expectations are high.

The average student taking C++, and especially if it's their first language, could not complete this assignment in less than a day -- believe me, I have taught C++. In the best case scenario for a good student (everything has been described to them, taught, sample programs provided, etc.). maybe a day.

Regards,

Paul McKenzie