Initial data commit

Task/Mutual-recursion/D/mutual-recursion.d

@@ -0,0 +1,14 @@
+import std.stdio, std.algorithm, std.range;
+
+int male(in int n) pure nothrow {
+    return n ? n - male(n - 1).female : 0;
+}
+
+int female(in int n) pure nothrow {
+    return n ? n - female(n - 1).male : 1;
+}
+
+void main() {
+    20.iota.map!female.writeln;
+    20.iota.map!male.writeln;
+}