RE: [Dev-C++] recursion

[<tel...@ya...>]

the thing with factorials is, that it's recursively
horrible since the numbers get very big very quicky,
ie the space allocation required will be massive.
before you even hit 13! or factorial(13) you exceed
the limit for the max value for integers.
(2,147,483,647)  (
http://www.newdream.net/~sage/old/numbers/fact.htm )
of course you could then use floats or double data
types etc, but the thing is, iteratively, the space is
set aside perhaps once for the factorial, one counter,
and once for the answer.

e.g. 
int factorial;
int answer=1;
int i=0;

/*assign factorials, cater for 0!=1 exception */

while (i<factorial)
{
    answer=answer*(factorial-i);
    i++;
}

/* then cout or printf or fstream of whatever u want
to do with it.. */

recursively however, as mentioned, it works through
stack, thing is, each stack level is sorta like the
'run time embodiement' of the called function. 
sorry, not too good @ this yet... :(

basic thing i'm getting @ is, each time the recursed
function is called, then the data is passed as it
would to any other function, and passing all that data
around is obviously gonna be a detriment to
performance as has been mentioned.

there are things that work better recursively, one
example is euclid's agorithm. google search it if u
have to, altho i assume most of you would know what it
is.

last thing, i cant think of an example, but i think
any recursion can be handled with a loop, but not all
loops can be done via recursion...

i dunno, how was i?? please lemme know if i dont know
jack :P

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