Sync

Task/Ackermann-function/Elena/ackermann-function.elena

@@ -1,33 +1,30 @@
-#define std'dictionary'*.
-#define std'patterns'*.
-
-#subject m, n.
+#define system.
 
 // --- Ackermann function ---
 
-#symbol Ackermann &m:anM &n:anN =
+#symbol ackermann = &&:m:n
 [
-    #if anM
-        ifequal:0 [ ^ anN + 1. ]
-        | greater:0 ?
-        [
-            #if anN
-                ifequal:0 [ ^ Ackermann &&m:(anM - 1) &n:1. ]
-                | greater:0 ? [ ^ Ackermann &&m:(anM - 1) &n:(Ackermann &&m:anM &n:(anN - 1)). ].
-        ].
-
-    control fail.
+    m =>
+       0 ? [ n + 1 ]
+       > 0 ? [
+              n => 0 ? [ $self:(m - 1):1 ]
+                       > 0 ? [ $self:(m - 1):($self:m:(n-1)) ]
+           ]
 ].
 
-#symbol Program =
+#symbol program =
 [
-    loop &&from:0 &to:3 run: anM =
+    #var n := ackermann:3:5.
+
+    control from:0 &to:3 &do: &&:i
     [
-        loop &&from:0 &to:5 run: anN =
+        control from:0 &to:5 &do: &&:j
         [
-            'program'output << "A(" << anM << "," << anN << ")=" << (Ackermann &&m:anM &n:anN) << "%n".
+            console << "A(" << i << "," << j << ")=" << (ackermann:i:j).
+
+            console writeLine.
         ].
     ].
 
-    'program'Input get.
+    console readChar.
 ].