Iteration v. Recursion...

[crptcblade]

Can some explain the difference between the two?

[filburt1]

Recursion: a function calling itself
Iteration: a loop such as For, While, etc.

[Megatron]

They're two completely different things. Recrusion is when a function calls itself, and iteration is one repetition of a sequence of instructions/events (e.g. in a loop, one iteration is once through the code in the loop)

[crptcblade]

Thanks

[filburt1]

Originally posted by filburt1
Recursion: a function calling itself
Iteration: a loop such as For, While, etc.

Examples:

// recursion:
int stuff(int x)
{
    if (x == 0) return 0;
    else return stuff(x - 1);
}

// iteration
int someValue = 0;
for (int i = 0; i < x, i++)
{
    someValue += i
}

Both return (except for the billions of bugs I didn't notice ) the sum from 0 to x.

[Zaei]

The recursion example looks like it returns 0 =).

stuff(4)            returns 0
return (4-1)     returns 0 ^
return (3-1)     returns 0 ^
return (2-1)     returns 0  ^
return (1-1) -> returns 0  ^

Z.

[edit]
It does, the code should look like:

int stuff(int x)  {
    if(x == 0) return 0;
    else return x + stuff(x-1);
}

[filburt1]

Heh, I told you there'd be bugs. But the basic concept is there.

[Zaei]

Quite =).

Z.