Something I can figure out how to solve the following problem:
There is a range of 360 files, which is divided into 30 elements into 12 parts.
Next is the file number, i.e. a number in the range from 1 to 360. The range from 1 - 30 corresponds to the 1st part, the range from 31 - 60 corresponds to the 2nd part, the range from 61 - 90 corresponds to the 3rd part, ..., the range from 331 - 360 corresponds to the 12-part.
How can knowing the file index (1 ... 360) arithmetically determine the index of the part to which it refers (1..12)?
