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Task/Ackermann-function/Nim/ackermann-function-1.nim

@@ -0,0 +1,7 @@
+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))

Task/Ackermann-function/Nim/ackermann-function-2.nim

@@ -0,0 +1,32 @@
+from strutils import parseInt
+
+proc ackermann(m,n: int): int =
+  var res: int
+  if m == 0:
+    res += n + 1
+  elif m > 0 and n == 0:
+    res += ackermann(m-1, 1)
+  elif m > 0 and n > 0:
+    res += ackermann(m-1, ackermann(m, n-1))
+  return res
+
+proc getnumber(): int =
+  try:
+    parseInt(readLine(stdin))
+  except EInvalidValue:
+    echo("Please enter an integer: ")
+    getnumber()
+
+echo("First number please: ")
+var first: int = getnumber()
+while first < 0:
+  echo("Please enter a non-negative integer value.")
+  first = getnumber()
+
+echo("Second number please: ")
+var second: int = getnumber()
+while second < 0:
+  echo("Please enter a non-negative integer value.")
+  second = getnumber()
+
+echo("Result: " & $ackermann(first, second))