From ce1cb4aee69363f214b710a1fe6d631971e9bf9a Mon Sep 17 00:00:00 2001 From: Luca Ferrari Date: Sat, 9 Oct 2021 17:25:47 +0200 Subject: Removed unused variable. --- challenge-133/luca-ferrari/raku/ch-2.p6 | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/challenge-133/luca-ferrari/raku/ch-2.p6 b/challenge-133/luca-ferrari/raku/ch-2.p6 index 0af9fa5cd0..d2aaf350f4 100644 --- a/challenge-133/luca-ferrari/raku/ch-2.p6 +++ b/challenge-133/luca-ferrari/raku/ch-2.p6 @@ -1,31 +1,37 @@ #!raku +# a lazy list of all prime numbers my @PRIMES = grep {.is-prime}, 1..*; +# divide a number into a list of its own factors multi do-factor( 1 ) { (1) } multi do-factor( Int $n where { $n > 1 } ) { - my ( $pos, $needle ) = 0, $n; - + my $needle = $n; my @factors; for @PRIMES -> $current-factor { + # stop if we got a bigger number last if $current-factor > $needle; + + # skip if the number is not a divisor of what we are searching for next unless $needle %% $current-factor; # if here, it is a good factor @factors.push: $current-factor; + # compute the remainder $needle /= $current-factor; } - @factors; + @factors.sort; } - +# It is a smith number if the sum of the digits +# is the sum of the factors sub is-smith-number( Int $n where { $n > 0 } ) { return $n.comb.sum == do-factor( $n ).sum; } -- cgit