10!

[Underdogger]

I use 4 Function to calculate this topic,only For Loop got wrong ~

While Loop ✓

$sum = sum(10)
Msgbox(0,"Total","Total:"&$sum)
Func sum($x)
$loop = 1
$y = 10
While $loop
$y = $y - 1
$x = $x * $y
If $y == 1 Then $loop = 0
WEnd
Return $x
EndFunc

Recursion ✓

$sum = sum(10)
Msgbox(0,"Total","Total:"&$sum)
Func sum($x)
If $x = 1 Then
Return 1
Else
Return $x * sum($x - 1)
EndIf
EndFunc

Do Loop ✓

$sum = sum(10)
Msgbox(0,"Total","Total:"&$sum)
Func sum($x)
$y = 10
Do
$y = $y - 1
$x = $x * $y
Until $y == 1
Return $x
EndFunc

For Loop ✖

$sum = sum(10)
Msgbox(0,"Total","Total:"&$sum)
Func sum($x)
$y = 10
For $i = 10 To 1 Step - 1
$y = $y - 1
$x = $x * $y
Next
Return $x
EndFunc

[water]

Change line

For $i = 10 To 1 Step -1

to

For $i = 10 To 2 Step -1

Because if you go down to 1 and then subtract 1 you multiply with 0. Edited January 21, 2013 by water

[Xenobiologist]

$sum = sum(10)
MsgBox(0, "Total", "Total:" & $sum)
Func sum($x)
$y = 10
For $i = 10 To 1 Step -1
$y -= 1
$x += $x * $y
Next
Return $x
EndFunc ;==>sum

[guinness]

#include <Constants.au3>

Local $iValue = Factorial(10)
MsgBox($MB_SYSTEMMODAL, '', 'Total: ' & $iValue)

Func Factorial($x)
    Local $y = $x
    For $i = 1 To $y - 1
        $x *= $i
    Next
    Return $x
EndFunc   ;==>Factorial

Edited January 23, 2013 by guinness

[Underdogger]

Thanks for the tutorial~ I got it!!!

[guinness]

I think I learnt something too, though I won't let you know what!

[Underdogger]

I think I learnt something too, though I won't let you know what!

guinness,Your tutorials are all helpful for me

[JohnQSmith]

Not to be pedantic, but your function should be called "factorial()", not "sum()".

[guinness]

Why I love 52!

So how many ways can you order all the 52 cards in a pack?

The sum is 52x51x50x49x48....x4x3x2x1 and the answer is roughly:

80,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000

That's an 8 with 67 zeros after it.

To put this in perspective, the dinosaurs died out 65,000,000 years ago, and the age of the earth is just 4,500,000,000 years. Now suppose everybody in the world was to arrange packs of cards at the rate of one per second, it would take 600,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 years to get all the combinations! That's why you're VERY unlikely ever to shuffle a pack of cards the same way twice.

Source: http://murderousmaths.co.uk/cardperms.htm

[jchd]

52! = 80658175170943878571660636856403766975289505440883277824000000000000

(a LOT more!)

[guinness]

Yeh, I don't know why they didn't post the correct value, as 'roughly' isn't a couple of units here or there.

[jchd]

True, I'd love 1% of 1‰ of 1‱ of the absolute value of the difference, even in ¥.