Merge pull request #5783 from andemark/branch-for-challenge-156

Branch for challenge 156

2 files changed, 48 insertions, 0 deletions

diff --git a/challenge-156/mark-anderson/raku/ch-1.raku b/challenge-156/mark-anderson/raku/ch-1.raku
new file mode 100644
index 0000000000..9d83cfd997
--- /dev/null
+++ b/challenge-156/mark-anderson/raku/ch-1.raku
@@ -0,0 +1,10 @@
+#!/usr/bin/env raku
+
+use Test;
+
+is-deeply (1..*).grep(&pernicious).head(10), (3, 5, 6, 7, 9, 10, 11, 12, 13, 14);
+
+sub pernicious($n)
+{
+    $n.base(2).comb.sum.is-prime
+}  
diff --git a/challenge-156/mark-anderson/raku/ch-2.raku b/challenge-156/mark-anderson/raku/ch-2.raku
new file mode 100644
index 0000000000..086f163102
--- /dev/null
+++ b/challenge-156/mark-anderson/raku/ch-2.raku
@@ -0,0 +1,38 @@
+#!/usr/bin/env raku
+
+use Test;
+use Prime::Factor;
+
+nok weird(12);
+nok weird(360);
+nok weird(420);
+
+ok  weird(70);
+ok  weird(836);
+ok  weird(7192);
+ok  weird(10792);
+ok  weird(12670);
+ok  weird(14770);
+
+sub weird($n)
+{
+    my @p = proper-divisors($n);
+    return 0 if @p.sum <= $n;
+    return + not subset-sum($n, @p);
+}
+
+sub subset-sum($sum, @n)
+{
+    my @a = 1, |(0 xx $sum);
+    @a[@n.head] = 1;
+
+    for @n.skip -> $n
+    {
+        for ($n..$sum).reverse -> $i
+        {
+            @a[$i] = @a[$i-$n] unless @a[$i]
+        }
+    }
+
+    @a.tail
+}