update

Task/Factorial/D/factorial.d

@@ -1,15 +1,15 @@
 import std.stdio, std.algorithm, std.metastrings, std.range;
 
 // iterative
-int factorial(int n) {
-    int result = 1;
+long factorial(long n) {
+    long result = 1;
     foreach (i; 1 .. n + 1)
         result *= i;
     return result;
 }
 
 // recursive
-int recFactorial(int n) {
+long recFactorial(long n) {
     if (n == 0)
         return 1;
     else
@@ -17,13 +17,13 @@ int recFactorial(int n) {
 }
 
 // functional-style
-int fact(int n) {
+long fact(long n) {
     return iota(1, n + 1).reduce!q{a * b}();
 }
 
 // tail recursive (at run-time, with DMD)
-int tfactorial(int n) {
-    static int facAux(int n, int acc) {
+long tfactorial(long n) {
+    static long facAux(long n, long acc) {
         if (n < 1)
             return acc;
         else

Task/Factorial/Eiffel/factorial.e

@@ -0,0 +1,49 @@
+note
+	description: "recursive and iterative factorial example of a positive integer."
+
+class
+	FACTORIAL_EXAMPLE
+
+create
+	make
+
+feature -- Initialization
+
+	make
+		local
+			n: NATURAL
+		do
+			n := 5
+			print ("%NFactorial of " + n.out + " = ")
+			print (recursive_factorial (n))
+		end
+
+feature -- Access
+
+	recursive_factorial (n: NATURAL): NATURAL
+			-- factorial of 'n'
+		do
+			if n = 0 then
+				Result := 1
+			else
+				Result := n * recursive_factorial (n - 1)
+			end
+		end
+
+	iterative_factorial (n: NATURAL): NATURAL
+			-- factorial of 'n'
+		local
+			v: like n
+		do
+			from
+				Result := 1
+				v := n
+			until
+				v <= 1
+			loop
+				Result := Result * v
+				v := v - 1
+			end
+		end
+
+end

Task/Factorial/Julia/factorial.julia

@@ -1,4 +1,3 @@
-# this is just a copy from the combinatorics.jl module of the Julia standard library
 function factorial(n::Integer)
     if n < 0
         return zero(n)
@@ -9,8 +8,3 @@ function factorial(n::Integer)
     end
     return f
 end
-
-load("bigint.jl")  #use BigInt to avoid overflow for large values of n
-n=BigInt(30)
-factorial(n)
-265252859812191058636308480000000

Task/Factorial/Run-BASIC/factorial.run

@@ -0,0 +1,19 @@
+for i = 0 to 100
+   print " fctrI(";right$("00";str$(i),2); ") = "; fctrI(i)
+   print " fctrR(";right$("00";str$(i),2); ") = "; fctrR(i)
+next i
+end
+
+function fctrI(n)
+fctrI = 1
+ if n >1 then
+  for i = 2 To n
+    fctrI = fctrI * i
+  next i
+ end if
+end function
+
+function fctrR(n)
+fctrR = 1
+if n > 1 then fctrR = n * fctrR(n -1)
+end function