Merge pull request #488 from randyl/week20

Solutions for challenge 1 and 2

2 files changed, 29 insertions, 0 deletions

diff --git a/challenge-020/randy-lauen/perl6/ch-1.p6 b/challenge-020/randy-lauen/perl6/ch-1.p6
new file mode 100644
index 0000000000..5c23588b8c
--- /dev/null
+++ b/challenge-020/randy-lauen/perl6/ch-1.p6
@@ -0,0 +1,8 @@
+#!/usr/bin/env perl6
+
+# Write a script to accept a string from command line and split it on change of character.
+# For example, if the string is “ABBCDEEF”, then it should split like “A”, “BB”, “C”, “D”, “EE”, “F”.
+
+sub MAIN( Str $text ) {
+    say $text.comb(/(.) {} $0*/).join(',');
+}
diff --git a/challenge-020/randy-lauen/perl6/ch-2.p6 b/challenge-020/randy-lauen/perl6/ch-2.p6
new file mode 100644
index 0000000000..1cd638e758
--- /dev/null
+++ b/challenge-020/randy-lauen/perl6/ch-2.p6
@@ -0,0 +1,21 @@
+#!/usr/bin/env perl6
+
+# Write a script to print the smallest pair of Amicable Numbers.
+
+say amicable-numbers.first;
+
+sub amicable-numbers {
+    return lazy gather {
+	my %seen;
+	for 1 .. Inf -> $i {
+	    my $key = ($i, sum proper-divisors( $i )).sort.join(',');
+	    take $key if %seen{ $key }:exists;
+	    %seen{ $key } = 1;
+	}
+    };
+}
+
+sub proper-divisors( $i ) {
+    return (1 .. $i-1).grep: { $i %% $_ };
+}
+