A-M baby

Task/Mutual-recursion/Perl/mutual-recursion.pl

@@ -0,0 +1,13 @@
+use strict;
+use warnings;
+
+# For mutually recursive functions,
+# predeclaring is probably a good idea.
+sub M; sub F;
+
+sub F { my $n = shift; $n ? $n - M F $n-1 : 1 }
+sub M { my $n = shift; $n ? $n - F M $n-1 : 0 }
+
+for my $f (\&F, \&M) {
+    print join(' ', map $f->($_), 0 .. 19), "\n";
+}