[AccessD] OT: Friday Puzzles

Thank you, Susan and Drew - your lovely chat (and Drew's original code)
forced me to try to find a math based solution ;) - here it's (C#) (please
corrent me if this solution will happen to be wrong):

1) Using lambda expressions:

public static int GetSurvivorNumberUsingFunctionalProgramming(int arraySize)
{
    Func<int, int, int> survivorNumber = null;
    survivorNumber =
        (lineSize, power) =>
            Math.Pow(2, power) > lineSize / 2 ?
            (int)Math.Pow(2, power) :
            survivorNumber(lineSize, power + 1);
    return survivorNumber(arraySize, 1);
}

2) Using iteration:

public static int GetSurvivorNumberUsingIteration(int arraySize)
{
    int power = 0;
    while (Math.Pow(2, ++power) <= arraySize / 2) ;
    return (int)Math.Pow(2, power); 
}

3) Using recursion:

public static int GetSurvivorNumberUsingRecursion(int arraySize)
{
    return GetSurvivorNumberUsingRecursion(arraySize, 1);  
}
public static int GetSurvivorNumberUsingRecursion(int arraySize, int power)
{
    if (Math.Pow(2, power) > arraySize / 2) 
        return (int)Math.Pow(2, power);
    return GetSurvivorNumberUsingRecursion(arraySize, power + 1);  
}

One can make similar iterative and recursive coding solutions using VBA.

Although C#'s/VB.NET's functional programming approach is more
powerful/scalable as modern compilers can compile, build and "automagically"
distribute execution of functional code blocks on several processor cores...

Thank you Arthur for this puzzle - it forced me to start learning C#
functional programming...

--Shamil

P.S. Here is how folks cancluate factorials using c# functional programming
(look at the bottom of this topic as it has really simple recursive
solution):

http://blogs.msdn.com/madst/archive/2007/05/11/recursive-lambda-expressions.
aspx

-----Original Message-----
From: accessd-bounces at databaseadvisors.com
[mailto:accessd-bounces at databaseadvisors.com] On Behalf Of Susan Harkins
Sent: Saturday, April 24, 2010 1:57 AM
To: Access Developers discussion and problem solving
Subject: Re: [AccessD] OT: Friday Puzzles

==========Drew, can you GET any geekier??????????? ;) 

Susan H. 
--