Mutual recursion: Difference between revisions

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@@ Line 1,327: / Line 1,327: @@
 =={{header|Java}}==
+Replace translation (that doesn't compile) with a Java native implementation.
-{{trans|C}}
+<lang java>
-<lang java5>public static int f(final int n)
+import java.util.HashMap;
-{
+import java.util.Map;
- return n == 0 ? 1 : n - m(f(n - 1));
-}
-public static int m(final int n)
+public class MutualRecursion {
-{
-  return n == 0 ? 0 : n - f(m(n - 1));
-}
-public static void main(final String args[])
+    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 < 20; i++)
+        for (int i = 0; i < max; i++) {
-  System.out.println(f(i));
- System.out.println();
+            System.out.printf("  f(%d) = %d%n", i, f(i));
- for (i = 0; i < 20; i++)
+        }
-  System.out.println(m(i));
+        System.out.printf("First %d values of the Male sequence:  %n", max);
+        for (int i = 0; i < 20; i++) {
-}</lang>
+            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;
+    }
+}
+</lang>
+{{out}}
+First 20 values of the Female sequence:
+  f(0) = 1
+  f(1) = 1
+  f(2) = 2
+  f(3) = 2
+  f(4) = 3
+  f(5) = 3
+  f(6) = 4
+  f(7) = 5
+  f(8) = 5
+  f(9) = 6
+  f(10) = 6
+  f(11) = 7
+  f(12) = 8
+  f(13) = 8
+  f(14) = 9
+  f(15) = 9
+  f(16) = 10
+  f(17) = 11
+  f(18) = 11
+  f(19) = 12
+First 20 values of the Male sequence:
+  m(0) = 0
+  m(1) = 0
+  m(2) = 1
+  m(3) = 2
+  m(4) = 2
+  m(5) = 3
+  m(6) = 4
+  m(7) = 4
+  m(8) = 5
+  m(9) = 6
+  m(10) = 6
+  m(11) = 7
+  m(12) = 7
+  m(13) = 8
+  m(14) = 9
+  m(15) = 9
+  m(16) = 10
+  m(17) = 11
+  m(18) = 11
+  m(19) = 12
 =={{header|JavaScript}}==