exercism-perl5

commit 1b881234def2a09fbf64865f959ab45e658aaa30
parent 9f372bd9e5a26b55c1272d181d18b5abe090ee84
Author: Samir Parikh <noreply@samirparikh.com>
Date:   Wed, 22 Dec 2021 15:30:21 +0000

update Sublist.pm

Diffstat:
M
sublist/Sublist.pm
 | 
18
++++++++++++++----

1 file changed, 14 insertions(+), 4 deletions(-)
diff --git a/sublist/Sublist.pm b/sublist/Sublist.pm
@@ -5,20 +5,30 @@ use v5.22;
 use Exporter qw<import>;
 our @EXPORT_OK = qw<compare_lists>;
 
-sub a_within_b {
+sub a_within_b2 {
   my ($a, $b) = @_;
   my @a = @{$a};
   my @b = @{$b};
   foreach my $element (@a) {
-    #print "checking $_ within @b ... ";
-    #my $found = grep { /$_/ } @b;
-    #say "found $found";
     return 0 unless (grep /^$element$/, @b); # grep needs expr that evaluates
                                              # to true or false
   }
   return 1;
 }
 
+sub a_within_b { # assume @a <= @b
+  my ($a, $b) = @_;
+  my @a = @{$a};
+  my @b = @{$b};
+  # check to see if first element of @a is in @b
+  my @idx = grep { $b[$_] eq $a[0] } 0 .. $#b;
+  return 0 unless (@idx);
+  for (my $a_idx=1, my $b_idx=$idx[0]+1; $a_idx<=$#a; $a_idx++, $b_idx++) {
+    return 0 unless ($a[$a_idx] eq $b[$b_idx]);
+  }
+  return 1;
+}
+
 sub compare_lists {
   my ($args) = @_;
   my @a = @{$args->{listOne}};