Works for me (Sun Solaris 5.7).
#First line, does as you said;
#uc sqrt hex chr lstat evals to 0, and open w/ string
#appends $ in front, so it opens $0, aka, yourself
die unless print keys %j and open uc sqrt hex chr lstat;
#~~<0>; 0 is the filehandle, so it reads in one line
#...the two negations(~~) cancel each other out, by the way
#You assign to @_, ignoring q, y, i, x, d, ;, and %
#(since, I presume, they aren't in the string you print out)
@_[0..100] = grep{!/[qyixd;%]/}split//,~~<0>;
#Simple enough, set output sep., to rec. sep, i.e., \n
$\=$/;
#Here's where the magic takes place.
print substr join(
#First, you map the @_ array that you assigned to for
#values 0..46; you sort them w/ z sub, dereferencing them
#And then you map them, again dereferencing
$&,
map{$$_[$[]}
sort{z($$a[1])<=>z($$b[1])}
map{[$_[$_],$_]}0..46),23;
#This function (taking your ref. to ref. to match, divided
# by ref. to ref. to ref. to match plus 1..$=, i.e., 1..60
#You've arranged it so as to pop the values you need to to
#get the correct result; It's difficult to figure out at
#first glance, however, so I'll leave it for someone else
#to inform us of.
sub z {@h[18,28,6,12,13,20,3,23,33,35,0,10,1,9,5,32,4,8,39,45,
29,14,15,40]= (1+\\///\\\//..$=);$h[pop];}
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