[rosalind] NWCK

Author: L. Grondin

rosalind/nwck-grondilu.pl

@@ -0,0 +1,18 @@
+use v6;
+say gather for lines[] -> $newick, $taxa, $ {
+    my ($a, $b) = $taxa.split: ' ';
+    my @token = $newick.comb: rx/ <.ident>+ | <[(),]> /;
+    Mu while @token.shift ne $a|$b;
+    my ($climbs, $descents) = 0 xx 2;
+    for @token {
+	last if $_ eq $a or $_ eq $b;
+	if /< , ) >/ {
+	    if $descents > 0 { $descents-- }
+	    else { $climbs++ }
+	}
+	if /< , ( >/ { $descents++ }
+    }
+    take $climbs + $descents;
+}
+
+# vim: ft=perl6