Merge pull request #4179 from seaker/master

challenge 115, Feng Chang's raku solutions

2 files changed, 35 insertions, 0 deletions

diff --git a/challenge-115/feng-chang/raku/ch-1.raku b/challenge-115/feng-chang/raku/ch-1.raku
new file mode 100755
index 0000000000..0634f261fc
--- /dev/null
+++ b/challenge-115/feng-chang/raku/ch-1.raku
@@ -0,0 +1,12 @@
+#!/bin/env raku
+
+sub MAIN(*@S) {
+    for @S.permutations -> @s {
+        if (^@s.elems).map({ @s[$_].substr(*-1) eq @s[($_+1) % @s.elems].substr(0,1) }).all {
+            put 1;
+            exit;
+        }
+    }
+
+    put 0;
+}
diff --git a/challenge-115/feng-chang/raku/ch-2.raku b/challenge-115/feng-chang/raku/ch-2.raku
new file mode 100755
index 0000000000..228ab113ea
--- /dev/null
+++ b/challenge-115/feng-chang/raku/ch-2.raku
@@ -0,0 +1,23 @@
+#!/bin/env raku
+
+sub largest-even(UInt:D $n --> UInt:D) {
+    my @d = $n.comb».UInt;                  # get all digits
+    my $last-digit = @d.grep(* %% 2).min;   # find the smallest even digit
+
+    my Bool $done = False;
+    @d .= grep({ $done or $_ != $last-digit ?? True !! do { $done = True; False }});    # filter out the found even digit, only once
+
+    (@d.sort({ $^b <=> $^a }).join ~ $last-digit).UInt      # 'print' the array, largest to smallest, at last, 'print' the found even digit
+}
+
+multi MAIN('test') {
+    use Test;
+
+    is largest-even(1026), 6210, '1,0,2,6 -> 6210';
+    is largest-even(1428), 8412, '1,4,2,8 -> 8412';
+    is largest-even(4176), 7614, '4,1,7,6 -> 7614';
+
+    done-testing;
+}
+
+multi MAIN(UInt:D $n) { put largest-even($n) }