Initial data commit

Task/Mutual-recursion/Java/mutual-recursion.java

@@ -0,0 +1,41 @@
+import java.util.HashMap;
+import java.util.Map;
+
+public class MutualRecursion {
+
+    public static void main(final String args[]) {
+        int max = 20;
+        System.out.printf("First %d values of the Female sequence:  %n", max);
+        for (int i = 0; i < max; i++) {
+            System.out.printf("  f(%d) = %d%n", i, f(i));
+        }
+        System.out.printf("First %d values of the Male sequence:  %n", max);
+        for (int i = 0; i < 20; i++) {
+            System.out.printf("  m(%d) = %d%n", i, m(i));
+        }
+    }
+
+    private static Map<Integer,Integer> F_MAP = new HashMap<>();
+
+    private static int f(final int n) {
+        if ( F_MAP.containsKey(n) ) {
+            return F_MAP.get(n);
+        }
+        int fn = n == 0 ? 1 : n - m(f(n - 1));
+        F_MAP.put(n, fn);
+        return fn;
+    }
+
+    private static Map<Integer,Integer> M_MAP = new HashMap<>();
+
+    private static int m(final int n) {
+        if ( M_MAP.containsKey(n) ) {
+            return M_MAP.get(n);
+        }
+        int mn = n == 0 ? 0 : n - f(m(n - 1));
+        M_MAP.put(n, mn);
+        return mn;
+    }
+
+
+}