solution for https://www.hackerrank.com/challenges/divisible-sum-pairs/

divisible-sum-pairs.pl

#!/usr/bin/perl
use Data::Dumper;
use strict;
use warnings;

# Complete the divisibleSumPairs function below.
sub divisibleSumPairs {
  my $n = shift;
  my $k = shift;
  my $ar = shift;
  my $sum = 0;
  my $r =0;
  for my $u1(0 .. ($n-1) ){
    for my $u2 ( ($u1+1) .. $n){
      $sum = $ar->[$u1] + $ar->[$u2];
      my $kk = $sum % $k;
      if (!($sum % $k)){
        $r++;
      }
    }
  }
  return $r;
}

open(my $fptr, '>', $ENV{'OUTPUT_PATH'});

my $nk = <>;
$nk =~ s/\s+$//;
my @nk = split /\s+/, $nk;

my $n = $nk[0];
$n =~ s/\s+$//;

my $k = $nk[1];
$k =~ s/\s+$//;

my $ar = <>;
$ar =~ s/\s+$//;
my @ar = split /\s+/, $ar;

$n--;

my $result = divisibleSumPairs $n, $k, \@ar;

print $fptr "$result\n";

close $fptr;