Mappability - Peak Seq (Convert chr1.fa to chr1b.out)

Question

[startup_biostar]

From this link http://archive.gersteinlab.org/proj/PeakSeq/Mappability_Map/Code/

I downloaded and tried to run as per the instruction in README file. But what is <merlen> as stated in the code?

How to compile this to get chr1.out file from chr1.fa?