Challenge #147 added by new enforcer 2colours :)

3 files changed, 31 insertions, 0 deletions

diff --git a/challenge-147/2colours/README b/challenge-147/2colours/README
new file mode 100644
index 0000000000..6894fbec08
--- /dev/null
+++ b/challenge-147/2colours/README
@@ -0,0 +1 @@
+Solution By Márton Polgár.
diff --git a/challenge-147/2colours/raku/ch-1.raku b/challenge-147/2colours/raku/ch-1.raku
new file mode 100755
index 0000000000..5757fef8da
--- /dev/null
+++ b/challenge-147/2colours/raku/ch-1.raku
@@ -0,0 +1,12 @@
+#!/usr/bin/env raku
+
+use experimental :cached;
+
+multi ltprimes(0, $) { ('') }
+multi ltprimes($digits, $base) is cached {
+  (1..^$base).map(*.base: $base) X~ ltprimes($digits-1, $base)
+    andthen .grep(&is-prime)>>.Int
+}
+
+
+(1..*).map(*.&ltprimes(10).Slip).head(20).say;
diff --git a/challenge-147/2colours/raku/ch-2.raku b/challenge-147/2colours/raku/ch-2.raku
new file mode 100755
index 0000000000..ca0dd53bd4
--- /dev/null
+++ b/challenge-147/2colours/raku/ch-2.raku
@@ -0,0 +1,18 @@
+#!/usr/bin/env raku
+
+sub is-pentagon($c) { (1+sqrt(1+24*$c))%%6 }
+
+sub P($n) { $n*(3*$n-1) div 2 #`(make rationals faster, pretty please) }
+
+OUTSIDE:
+for 1..Inf -> $bigger {
+  for 1..^$bigger -> $smaller {
+    my $bigger-p = P($bigger);
+    my $smaller-p = P($smaller);
+    #my ($bigger-p, $smaller-p) = (P($bigger), P($smaller)); eliminate the runtime overhead of this destructuring, pretty please 
+    if is-pentagon($bigger-p + $smaller-p) && is-pentagon($bigger-p - $smaller-p) {
+      say "P($bigger)=$bigger-p and P($smaller)=$smaller-p";
+      last OUTSIDE;
+    }
+  }
+}