Currently it's enough with reading carefully the description.

The current description is fine with this.

The current description is fine

Done

Not a kata suggestion.

I think this can be an instructive experience. It has been for me.

So you probably need to find another way to solve this. You are on the right track.

with value type "unsigned long long" in c++, when the number is more than 67, c++ doesn't support because the factorial of this number show like infinity.

On the contrary, I think this kata is a good exercise to develop some skills.

Please use a spoiler flag when you post code somewhere, and use markdown tags to format your code or it's no usable, see there : https://docs.codewars.com/training/troubleshooting/

Your code throws a syntax error.

Ok. Thanks!)