Optimize slightly ch-1.pl

1 files changed, 11 insertions, 7 deletions

diff --git a/challenge-107/wlmb/perl/ch-1.pl b/challenge-107/wlmb/perl/ch-1.pl
index 3466ea1f98..7e60c30114 100755
--- a/challenge-107/wlmb/perl/ch-1.pl
+++ b/challenge-107/wlmb/perl/ch-1.pl
@@ -16,30 +16,34 @@ exit unless $howmany > 0;
 my @results;
 my $largest_base=36; #allows ten decimal digits and 26 letters
 my @letter_from_digit=(0..9,'a'..'z');
-my $base=2;
-
+my $base=1;
  RESULT:
     while($howmany>@results){
 	++$base;
 	last RESULT if $base>$largest_base;
 	for my $firstdigit(1..$base-1){
-	    try([$firstdigit],0,$base, $firstdigit);
+	    my $have=[(0)x$base]; #initialize digits in number
+	    $have->[$firstdigit]++;
+	    try([$firstdigit],0,$base, $firstdigit, $have);
 	    last RESULT if @results==$howmany;
 	}
 }
 my $n=1;
 foreach(@results){
     say sprintf("%2d- Base %2d:  %s", $n++, scalar @$_,
-                join('', map {$letter_from_digit[$_]} @$_));
+		join('', map {$letter_from_digit[$_]} @$_));
 }
 sub try {
-    my ($current,$position,$base, $sum)=@_;
+    my ($current,$position,$base, $sum, $had)=@_;
     if($position==$base-1){
 	push @results, $current if check($current);
 	return;
     }
-    for my $digit(0..$base-$sum){
-	try([(@$current,$digit)], $position+1, $base, $sum+$digit);
+    ++$position;
+    for my $digit($had->[$position]..$base-$sum){
+	my $have=[@$had]; # copy
+	$have->[$digit]++;
+	try([(@$current,$digit)], $position, $base, $sum+$digit, $have);
     }
 }