+Working from left-to-right if no digit is exceeded by the digit to its left it is called an increasing number; for example, 134468.

+Similarly if no digit is exceeded by the digit to its right it is called a decreasing number; for example, 66420.

+We shall call a positive integer that is neither increasing nor decreasing a "bouncy" number; for example, 155349.

+Clearly there cannot be any bouncy numbers below one-hundred, but just over half of the numbers below one-thousand (525) are bouncy. In fact, the least number for which the proportion of bouncy numbers first reaches 50% is 538.

+Surprisingly, bouncy numbers become more and more common and by the time we reach 21780 the proportion of bouncy numbers is equal to 90%.

+Find the least number for which the proportion of bouncy numbers is exactly 99%.

+ my $s = join "",sort { $a <=> $b } split//,$n;

+ $counts[($n eq $s) || ($n eq scalar(reverse($s))) || 0]++;

+ if ($counts[1] * 100 == $n)

+ print "Least n = $n\n";