TWC244

Challenge Link

Task1

for each element we count the elements which are smaller that it:

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

sub count_smaller{
  my ($arr) = @_;
  map{my $e = $_;scalar grep{$_ < $e}@$arr}@$arr;
}

printf "(%s)\n",join ',',count_smaller([8,1,2,2,3]);
printf "(%s)\n",join ',',count_smaller([6,5,4,8]);
printf "(%s)\n",join ',',count_smaller([2,2,2]);

Task2

We iterate all the subsets of of the list and accumulate the sum according to the given rules:

#!/usr/bin/env perl
use strict;
use warnings;
use List::Util qw(min max);
use Algorithm::Combinatorics qw(subsets);

sub group_hero{
  my $sum = 0;
  my $it = subsets($_[0]);
  while(my $c = $it->next){
    $sum += (max(@$c) ** 2) * min(@$c) if @$c;
  }
  $sum
}

printf "%d\n", group_hero([2,1,4]);