September 2017 Update

Task/Ackermann-function/Nim/ackermann-function.nim

@@ -0,0 +1,25 @@
+from strutils import parseInt
+
+proc ackermann(m, n: int64): int64 =
+  if m == 0:
+    result = n + 1
+  elif n == 0:
+    result = ackermann(m - 1, 1)
+  else:
+    result = ackermann(m - 1, ackermann(m, n - 1))
+
+proc getNumber(): int =
+  try:
+    result = stdin.readLine.parseInt
+  except ValueError:
+    echo "An integer, please!"
+    result = getNumber()
+  if result < 0:
+    echo "Please Enter a non-negative Integer: "
+    result = getNumber()
+
+echo "First non-negative Integer please: "
+let first = getNumber()
+echo "Second non-negative Integer please: "
+let second = getNumber()
+echo "Reslut: ", $ackermann(first, second)