The answer is BORROMEO The corresponding square is ST. CHARLES by Kiran Kedlaya This is a Perl script on which a substitution cipher has been performed on the letters (and the nonalphabetic characters are unchanged). Solve the cipher, run the program, and it prints out BORROMEO. (Decrypting the blurb by the same cipher gives #!perl, a comment placed at the top of a Perl script to tell a shell how to execute it.) Here is the decrypted script: @y=();push@y,scalar@y;push@y,scalar@y;shift@y;unshift@y,@y,@y; $z="@y";$z=~s/\s//g;pop@y;push@y,chr(@y*ord($z));push@y,chr$z;shift@y; $z=$z+scalar@y;shift@y;push@y,chr$z;push@y,chr$z;$z=join"",@y;print uc$z; chop$z;@y=(chr(ord($z)+length$z));push@y,substr$z,length index"",$z; unshift@y,chr ord($z)+hex$z;unshift@y,chr ord($y[index"",$z])-scalar@y; pop@y;print uc join"",@y;@y=sort@y;print ucfirst pop@y;