Solutions to Challenge 4 for Doug Schrag

2 files changed, 40 insertions, 0 deletions

diff --git a/challenge-004/doug-schrag/perl6/ch-1.p6 b/challenge-004/doug-schrag/perl6/ch-1.p6
new file mode 100644
index 0000000000..dc93ecece7
--- /dev/null
+++ b/challenge-004/doug-schrag/perl6/ch-1.p6
@@ -0,0 +1,27 @@
+use v6;
+
+my $chars = $*PROGRAM.slurp.chars;
+say pi-rat.Str.substr(0,$chars);
+say "$chars digits!";
+
+sub postfix:<!> ($n) { [*] 1..$n }
+sub f($k) {
+    FatRat.new: (4*$k)! * (1103 + 26390 * $k), ($k!)**4 * 396**(4*$k)
+}
+sub pi-rat () {
+    9801 * sqrt-rat(2, 1e-500) / 4
+    / [+] (^80).map: *.&f
+}
+
+multi sub sqrt-rat ($n where * > 0, $eps) {
+    my $base = $n.FatRat($eps);
+    my $r = sqrt($base).FatRat($eps);
+    my $est;
+    repeat {
+        $est = $r;
+        $r = ($base / $est + $est) / 2;
+    } while abs($r - $est) > $eps;
+
+    return $r;
+}
+multi sub sqrt-rat (0) { 0 }
diff --git a/challenge-004/doug-schrag/perl6/ch-2.p6 b/challenge-004/doug-schrag/perl6/ch-2.p6
new file mode 100644
index 0000000000..754f7849f6
--- /dev/null
+++ b/challenge-004/doug-schrag/perl6/ch-2.p6
@@ -0,0 +1,13 @@
+use v6;
+
+sub MAIN(:$file?, *@letters where *.all.chars == 1) {
+    say @letters;
+    my $file-handle = .IO with $file;
+    $file-handle ||= $*IN;
+    my $tiles = Bag.new(@letters>>.fc);
+    for $file-handle.lines>>.fc -> $word {
+        $word.comb.Bag (<=) $tiles
+            and say $word;
+    }
+
+}