$ perl -v | head -2 | tail -1
This is perl 5, version 36, subversion 0 (v5.36.0) built for cygwin-thread-multi

$ ./op_code.pl test_data
0.118364 read lines from disk and do RE.
0.094379 read lines from in-memory file and do RE.

$ ./op_code.pl test_data_Q
0.362871 read lines from disk and do RE.
399.115542 read lines from in-memory file and do RE.