can someone get me started on calculating n! I think i should use a for loop.

:confused:

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- 11-19-2002sonictn!
can someone get me started on calculating n! I think i should use a for loop.

:confused: - 11-19-2002the Wookie
where is the variable n used?

you need an equation

like

5 = 2 + n

or

2(n) + 12938109283109283 = 3094809384503985 - 11-19-2002Sang-drax
Hehe I think the Wooike misunderstood the question! :D

n! = 1 * 2 * 3 * ... * n

If you know how to write for-loops this should be a piece of cake. - 11-19-2002MrWizard
By definition n factorial is...

n! = n * (n - 1) * (n - 2) * ... 1

The one at the end comes from the base case of 0! which is equal to 1. Have fun. - 11-19-2002alpha
i think you mean n factorial. probably one of the easiest ways is to use a recursive function...try it, then post your code...

it shouldn't be too long... - 11-19-2002sonictn!
#include <iostream.h>

#include <stdio.h>

unsigned int f,x=0;

unsigned int factorial(unsigned int a);

int main(void)

{

int hold;

puts("Please enter an integer value: ");

scanf("%d", &x);

{2

f=factorial(x);

printf("%u factorial equals %u\n\n", x,f);

}

cin >> hold;

return 0;

}

unsigned int factorial(unsigned int a)

{

if(a==1)

{

return 1;

}

else

{

a *=factorial(a-1);

}

return a;

} - 11-19-2002Captain PenguinQuote:

*Originally posted by alpha*

**i think you mean n factorial. probably one of the easiest ways is to use a recursive function...try it, then post your code...**

it shouldn't be too long...

- 11-19-2002the WookieQuote:

*Originally posted by Sang-drax*

**Hehe I think the Wooike misunderstood the question! :D**

n! = 1 * 2 * 3 * ... * n

If you know how to write for-loops this should be a piece of cake.

i thought he meant like

"help me!"

:o - 11-19-2002alphaQuote:

*Originally posted by Captain Penguin*

**You don't need a recursive function for that..**

- 11-19-2002Sang-draxQuote:

*Originally posted by MrWizard*

**By definition n factorial is...**

n! = n * (n - 1) * (n - 2) * ... 1

The one at the end comes from the base case of 0! which is equal to 1. Have fun.

When z is a negative integer, z! = infinity - 11-19-2002moiQuote:

*Originally posted by alpha*

**I know you don't need a recursive function for it, I think its a cooler way of doing it though...and possibly shorter, im not sure because i haven't written factorial using a for loop since a few months ago...**

- 11-19-2002XSquaredQuote:

*Originally posted by Sang-drax*

**For fun, here's the definition of z! when z is a real or complex number:**

When z is a negative integer, z! = infinity

can you convert that to c code so i can understand it? :D - 11-19-2002Captain PenguinQuote:

*Originally posted by moi*

**cooler? who cares, its sloooooooooooow.**

Code:`int main()`

{

int n;

int ans = 1;

cin >> n;

for(int x = n; x > 0; x--)

{

ans = ans * x;

}

cout << ans;

}

- 11-19-2002alpha
okay, i didn't know it was that much slower. i recently just kindof taught myself recursion, so I like using it for the time being...I'll get over the phase, hehe...