Overclock.net › Forums › Software, Programming and Coding › Coding and Programming › Recursion and Iteration?
New Posts  All Forums:Forum Nav:

Recursion and Iteration?

post #1 of 3
Thread Starter 
I'm reading and watching some stuff posted on MIT about SICP (Structure and Interpretation of Computer Programs) and i tried googling this up but it seems like everyone has a different answer (or so i think) so im asking you guys this.

whats the difference between iteration and recursion?
post #2 of 3
To define recursion you must first understand recursion...haha, old computer science joke my teacher told us.

Iteration is how it sounds, iterating through the data and performing calculations or manipulations:

Code:
public int IterativeFactorial(int fact)
{
    
        int total; 

        if (fact <= 1)
        {
            return 1;
        }
        else
        {
            for(int i = 1; i < fact; i++)
            { 
                total *= fact;
            }
         }

         return total;
}
Recursion is a function that calls itself:

Code:
public int RecursiveFactorial(int fact)
{
        if (fact <= 1) 
        {
    return 1;
}
else 
        {
    return fact * RecursiveFactorial(fact - 1);
}
}
Notice how in this example of a factorial calculation, the function ends up calling itself if the number is greater than 1. In the iterative example, we iterate through all the data, and total up the factorial.

Understand?

Edit: Sorry if my iterative algorithm is wrong, I wrote this up quickly, and don't really have time to check for correctness
Edited by CovertCover - 12/31/10 at 6:39pm
My System
(13 items)
 
  
CPUMotherboardGraphicsRAM
Core i7-930 D0 3.8Ghz ASUS P6T SE PowerColor HD5870 1GB 6GB Corsair Dominator XMS3 8-8-8-20 1200Mhz 
Hard DriveOSMonitorPower
1TB Wester Digital Windows 7 Home 64bit Acer 23" XFX 850w Black Edtion 
Case
HAF 932 
  hide details  
Reply
My System
(13 items)
 
  
CPUMotherboardGraphicsRAM
Core i7-930 D0 3.8Ghz ASUS P6T SE PowerColor HD5870 1GB 6GB Corsair Dominator XMS3 8-8-8-20 1200Mhz 
Hard DriveOSMonitorPower
1TB Wester Digital Windows 7 Home 64bit Acer 23" XFX 850w Black Edtion 
Case
HAF 932 
  hide details  
Reply
post #3 of 3
Thread Starter 
yah, thx
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Coding and Programming
Overclock.net › Forums › Software, Programming and Coding › Coding and Programming › Recursion and Iteration?