first pass

2 files changed, 47 insertions, 0 deletions

diff --git a/challenge-144/james-smith/perl/ch-1.pl b/challenge-144/james-smith/perl/ch-1.pl
new file mode 100644
index 0000000000..97fe5b4e33
--- /dev/null
+++ b/challenge-144/james-smith/perl/ch-1.pl
@@ -0,0 +1,23 @@
+#!/usr/local/bin/perl
+
+use strict;
+
+use warnings;
+use feature qw(say);
+use Test::More;
+use Benchmark qw(cmpthese timethis);
+use Data::Dumper qw(Dumper);
+
+
+my $N = 1000;
+my @primes      = (2);
+my @semi_primes = (4);
+
+foreach my $p ( map { 1+2*$_ } 1..($N/4) ) {
+  map { ($p%$_)||(next) } @primes;
+  push @primes,$p;
+  push @semi_primes,grep {$_<=$N} map{$p*$_} @primes;
+}
+
+say for sort {$a<=>$b} @semi_primes;
+
diff --git a/challenge-144/james-smith/perl/ch-2.pl b/challenge-144/james-smith/perl/ch-2.pl
new file mode 100644
index 0000000000..024a36197b
--- /dev/null
+++ b/challenge-144/james-smith/perl/ch-2.pl
@@ -0,0 +1,24 @@
+#!/usr/local/bin/perl
+
+use strict;
+
+use warnings;
+use feature qw(say);
+use Test::More;
+use Benchmark qw(cmpthese timethis);
+use Data::Dumper qw(Dumper);
+
+my (@seq,%seq_hash);
+
+say "@{[ ulam(1,2,100) ]}";
+say "@{[ ulam(2,3,100) ]}";
+say "@{[ ulam(2,5,100) ]}";
+
+sub ulam {
+  my%seq_hash=map{$_,$_}my@seq=($_[0],my$n=$_[1]);
+  for(;scalar @seq<$_[2];++$n){
+    push@seq,$seq_hash{$n}=$n if 1==grep{2*$_<$n&&$seq_hash{$n-$_}}@seq;
+  }
+  @seq;
+}
+