ↄ is a language made up of all the programs that fail to compile as C programs. Depending on the line(s) of code that fails to compile as C, a different ↄ program is produced.
Divide the line number of the syntax error(s) by three. Based on the remainder:
Since each of these run very quickly, and none interact with the system in any other way, they can be hard to tell apart. And any C compiler that simply reports a C compilation error may also secretly be a ↄ interpreter.