a solution of 082.2 in raku

1 files changed, 32 insertions, 0 deletions

diff --git a/challenge-082/gugod/raku/ch-2.raku b/challenge-082/gugod/raku/ch-2.raku
new file mode 100644
index 0000000000..047c4e0c4d
--- /dev/null
+++ b/challenge-082/gugod/raku/ch-2.raku
@@ -0,0 +1,32 @@
+#!/usr/bin/env raku
+
+sub MAIN (Str $A, Str $B, Str $C) {
+    say interleaves($A, $B, $C) ?? 1 !! 0;
+}
+
+sub interleaves (Str $A, Str $B, Str $C) {
+    my @stash;
+    @stash.push([-1, -1]);
+
+    my $i = 0;
+    while $i < $C.chars && @stash.elems > 0 {
+        my $c = $C.substr($i++, 1);
+        my @stash2 = gather {
+            while @stash.elems > 0 {
+                my $it = @stash.pop();
+                my $a = $A.substr($it[0]+1, 1);
+                my $b = $B.substr($it[1]+1, 1);
+                if $c eq $a {
+                    take [$it[0]+1, $it[1]];
+                }
+                if $c eq $b {
+                    take [$it[0], $it[1]+1];
+                }
+            }
+        };
+
+        @stash = @stash2.unique(:with(&[eqv]));
+    }
+
+    return $i == $C.chars && @stash.elems > 0 && @stash[0][0].succ == $A.chars && @stash[0][1].succ == $B.chars;
+}