TWC352

Challenge Link

Task1

We return every string that is a substring of amother:

#!/usr/bin/env perl
use strict;
use warnings;
use List::Util qw(any);

sub match_string{
  my ($arr) = @_;
  my @res;
  foreach my $i(0..$#$arr) {
    my $x = $arr->[$i];
    foreach my $j(0..$#$arr) {
      my $y = $arr->[$j];
      if($i != $j && index($y,$x) != -1 && !any{$_ eq $x} @res) {
	push @res,$x;
	last
      }
    }
  }
  @res
}

printf "(%s)\n",join ', ',match_string(['cat','cats','dog','dogcat',
				       'dogcat','rat','ratcatdogcat']);
printf "(%s)\n",join ', ',
  match_string(['hello','hell','world','wor','ellow','elloworld']);
printf "(%s)\n",join ', ',
  match_string(['a', 'aa', 'aaa', 'aaaa']);
printf "(%s)\n",join ', ',
  match_string(['flower','flow','flight','fl','fli','ig','ght']);
printf "(%s)\n",join ', ',
  match_string(['car','carpet','carpenter','pet',
		'enter','pen','pent']);

Task2

We check if the accumulated binary number is divisible by 5 and accumulate the boolean results in an array:

#!/usr/bin/env perl
use strict;
use warnings;

sub binary_prefix{
  my @res;
  my $x = 0;
  foreach(@{$_[0]}){
    $x = ($x << 1 | $_) % 5;
    push @res,$x == 0 ? 1 : 0;
  }
  @res
}

printf "(%s)\n", join ', ', binary_prefix([0,1,1,0,0,1,0,1,1,1]);
printf "(%s)\n", join ', ', binary_prefix([1,0,1,0,1,0]);
printf "(%s)\n", join ', ', binary_prefix([0,0,1,0,1]);
printf "(%s)\n", join ', ', binary_prefix([1,1,1,1,1]);
printf "(%s)\n", join ', ', binary_prefix([1,0,1,1,0,1,0,0,1,1]);