Rule 2.B.b says the tilde ‘~’ (ASCII 126) sorts before other bytes, and before an empty string.
$ cat input7 1 1% 1.2 1~ ~ $ sort -V input7 ~ 1~ 1 1% 1.2
The sorting algorithm starts by breaking down the string into non-digit (rule 2) and digit parts (rule 3).
In the above input file, only the last line in the input file starts with a non-digit (‘~’). This is the first part. All other lines in the input file start with a digit – their first non-digit part is empty.
Based on rule 2.B.b, tilde ‘~’ sorts before other bytes and before the empty string – hence it comes before all other strings, and is listed first in the sorted output.
The remaining lines (‘1’, ‘1%’, ‘1.2’, ‘1~’) follow similar logic: The digit part is extracted (1 for all strings) and compares equal. The following extracted parts for the remaining input lines are: empty part, ‘%’, ‘.’, ‘~’.
Tilde sorts before all others, hence the line ‘1~’ appears next.
The remaining lines (‘1’, ‘1%’, ‘1.2’) are sorted based on previously explained rules.