Data update

Task/Factorial/Haskell/factorial-10.hs

@@ -0,0 +1,8 @@
+-- product of [a,a+1..b]
+productFromTo a b =
+  if a>b then 1
+  else if a == b then a
+  else productFromTo a c * productFromTo (c+1) b
+  where c = (a+b) `div` 2
+
+factorial = productFromTo 1

Task/Factorial/Haskell/factorial-5.hs

@@ -1,3 +1 @@
-factorial :: Integral -> Integral
-factorial 0 = 1
-factorial n = n * factorial (n-1)
+factorials = 1 : zipWith (*) factorials [1..]

Task/Factorial/Haskell/factorial-6.hs

@@ -1,5 +1,2 @@
-fac n
-    | n >= 0    = go 1 n
-    | otherwise = error "Negative factorial!"
-        where go acc 0 = acc
-              go acc n = go (acc * n) (n - 1)
+factorials = go 1 1 where
+    go n fac = f : go (n+1) (n*fac)

Task/Factorial/Haskell/factorial-7.hs

@@ -1,10 +1,3 @@
-{-# LANGUAGE PostfixOperators #-}
-
-(!) :: Integer -> Integer
-(!) 0 = 1
-(!) n = n * (pred n !)
-
-main :: IO ()
-main = do
-  print (5 !)
-  print ((4 !) !)
+factorial :: Integral -> Integral
+factorial 0 = 1
+factorial n = n * factorial (n-1)

Task/Factorial/Haskell/factorial-8.hs

@@ -1,8 +1,5 @@
--- product of [a,a+1..b]
-productFromTo a b =
-  if a>b then 1
-  else if a == b then a
-  else productFromTo a c * productFromTo (c+1) b
-  where c = (a+b) `div` 2
-
-factorial = productFromTo 1
+fac n
+    | n >= 0    = go 1 n
+    | otherwise = error "Negative factorial!"
+        where go acc 0 = acc
+              go acc n = go (acc * n) (n - 1)

Task/Factorial/Haskell/factorial-9.hs

@@ -0,0 +1,10 @@
+{-# LANGUAGE PostfixOperators #-}
+
+(!) :: Integer -> Integer
+(!) 0 = 1
+(!) n = n * (pred n !)
+
+main :: IO ()
+main = do
+  print (5 !)
+  print ((4 !) !)

Task/Factorial/Langur/factorial-1.langur

@@ -1,2 +1,2 @@
-val factorial = fn n: fold(fn{*}, 2 .. n)
+val factorial = fn n: fold(2 .. n, by=fn{*})
 writeln factorial(7)

Task/Factorial/M2000-Interpreter/factorial-2.m2000

@@ -0,0 +1,27 @@
+Cls , 0  ' 0 for non split display, eg 3 means we preserve the 3 top lines from scrolling/cla
+Report {
+	Factorial Task
+	Definitions
+               • The factorial of   0   (zero)   is defined as being   1   (unity).
+               • The   Factorial Function   of a positive integer,   n,   is defined as the product of the sequence:
+                                                                      n,   n-1,   n-2,   ...   1
+
+}
+Cls, row  ' now we preserve some lines (as row number return here)
+Module CheckIt {
+      m=bigInteger("1")
+      with m, "tostring" as m.toString
+      k=width-tab
+      For i=1 to 1000
+      if pos>tab then print
+      Print @(0), format$("{0::-4} :", i) ;
+      method m,"multiply", biginteger(i+"") as m
+      Report m.toString, k
+      ' Report stop at 2/3 of display lines, and wait mouse button or spacebar
+      ' we can flush the keyboard buffer and press space, so we get non stop display
+      ' Report didn't stop if we use the printer's layer.
+      while inkey$<>"": wait 1:end while
+      keyboard " "
+      Next i
+}
+Checkit

Task/Factorial/Retro/factorial.retro

@@ -1,2 +1,8 @@
-: <factorial> dup 1 = if; dup 1- <factorial> * ;
-: factorial dup 0 = [ 1+ ] [ <factorial> ] if ;
+:<factorial>
+  dup #1 -eq? 0; drop
+  dup n:dec <factorial> * ;
+
+:factorial
+  dup n:zero?
+  [ n:inc ]
+  [ <factorial> ] choose ;

Task/Factorial/YAMLScript/factorial.ys

@@ -1,4 +1,4 @@
-!yamlscript/v0
+!YS-v0
 
 defn main(n=10):
   say: "$n! -> $factorial(n)"