C Programming - Functions - Discussion

According to me, it is;

long fun(int num)
{
int i;
/* declare variable i as int.... */

long f=1;
/* declare and initialize variable f as long with value 1 */

for(i=1; i<=num; i++)
f = f * i;

/* for loop is used
Let's take an example...
-> 10 is given as arguments in the function fun...
[First Time]
- > i is initialized with 1 , 1<=10 ,condition true
- > f = 1*1
[Second Time]
- > i is incremented and becomes i = 2 , 2<=10 , condition true
- > f = 1*2 = 2

and further till i = 10, 10<=10 , condition true
- > f = 1* 2*3*4*5*6*7*8*9*10 */

return f;
/* because it returns an float variable .... */
}

@usha

If num =3 \* 3! = 6 *|
i=1 , f=1
Executes the for loop now i=1, 1<=3,post increment so i= 2 for next time

f= f*i =1*1 =1 --------returns f as 1
Next time after for loop
1*2 = 3-------------returns f as 2
After for loop
2*3 = 6 ---------------returns f as 6
Now for loops get failed in condition
So f=====6 \* ans *\

Suppose num=4;

In the program given that
>> f=1
>>for(i=1;i<=4;i++)
f=f*i;
let us evaluate the for loop
step 1: f=1*1=1
step 2: f=1*2=2
step 3: f=2*3=6
step 4: f=6*4=24

IN EACH STEP VALUE OF " f " is saved

So factorial of 4 is 24.

It gives the correct result, even if we put 0 value then also for loop won't work and we return the value of f and previously it is initialized to 1 and 0!=1.

So it works perfectly fine for 0 value also.

You can take any value for num. In for loop, the statement written, it will behave like factorial so answer is C. Take any value you will understand.

It does not calculate the factorial of all the numbers. 0! is not calculated so None of the above must be the correct answer.

How it calculate the factorial values here please explain step by step?

There is no 'main' function. Then, how it's execute?

In for loop, what is the value of num

How it calculates factorial values?