It's just the standard addition algorithm, with carry, where we add one each time.
I have a very simple question: What is the rule of counting?
For instance, how do we know that 64 comes after 63 or 90 comes after 89?
We do not memorize all the numbers, isnt it?
So there is a rule and I am looking forward to hearing the answers.
I have an answer for this but I really want to hear the ideas for the algorithm...