https://codeiq.jp/ace/yuki_hiroshi/q172

codeiq_172.pl

#!/usr/bin/env perl

use strict;
use warnings;

my @series = (0, 1);
my $f42 = fibonacci(42);
my $f43 = fibonacci(43);
print_count(42, 144);
print_count($f42, $f43);
exit;

sub fibonacci {
  my $i = shift;
	return $series[$i] if $#series >= $i;
	$series[$i] = fibonacci($i-2) + fibonacci($i-1);
	return $series[$i];
}

sub count {
	my($h, $w) = @_;
	die "error: height[$h] must be less than width[$w]\n" if $h >= $w;
	return $w % $h ? count($w % $h, $h) + 1 : 0;
}

sub print_count {
	my($h, $w) = @_;
	printf "%dx%d = %d\n", $h, $w, count($h, $w);
}