Translated the low memory version of the Go entry but showed only the first 50 self numbers. The machine for running this task (a Xeon E3110+8GB memory) is showing its age as, 1) took over 6 minutes to complete the Go entry, 2) not even able to run the other two Go alternative entries and 3) needed over 47 minutes to reach 1e6 iterations here. Anyway I will try this on an i5 box later to see how it goes.
# 20201127 Raku programming solution
my ( $st, $count, $i, $pow, $digits, $offset, $lastSelf, $done, @selfs) =
now, 0, 1, 10, 1, 9, 0, False;
# while ( $count < 1e8 ) {
until $done {
my $isSelf = True;
my $sum = (my $start = max ($i-$offset), 0).comb.sum;
loop ( my $j = $start; $j < $i; $j+=1 ) {
if $j+$sum == $i { $isSelf = False and last }
($j+1)%10 != 0 ?? ( $sum+=1 ) !! ( $sum = ($j+1).comb.sum ) ;
}
if $isSelf {
$count+=1;
$lastSelf = $i;
if $count ≤ 50 {
@selfs.append: $i;
if $count == 50 {
say "The first 50 self numbers are:\n", @selfs;
$done = True;
}
}
}
$i+=1;
if $i % $pow == 0 {
$pow *= 10;
$digits+=1 ;
$offset = $digits * 9
}
}
# say "The 100 millionth self number is ", $lastSelf;
# say "Took ", now - $st, " seconds."