DifferenceOfSquares.pm (497B) - raw
1 package DifferenceOfSquares; 2 use strict; 3 use warnings; 4 use Exporter qw<import>; 5 our @EXPORT_OK 6 = qw<square_of_sum sum_of_squares difference_of_squares>; 7 8 sub square_of_sum { 9 my ($number) = @_; 10 my $sum; 11 $sum += $_ foreach (1 .. $number); 12 return $sum * $sum; 13 } 14 15 sub sum_of_squares { 16 my ($number) = @_; 17 my $sum; 18 $sum += $_ * $_ foreach (1 .. $number); 19 return $sum; 20 } 21 22 sub difference_of_squares { 23 my ($number) = @_; 24 return square_of_sum($number) - sum_of_squares($number); 25 } 26 27 1;