Thread: returning random value.

Right. Try:

Code:

#include <stdio.h>

int sumdig(int num);

int main(void)
{
    int a;
    a = sumdig(12345);
    printf("%d\n", a);
    return 0;
}

int sumdig(int num)
{
    static int sum;
    int a, b;
    a = num % 10;
    b = (num - a) / 10;
    sum = sum + a;
    if (b != 0)
        sumdig(b);
    return(sum);
}

This is essentially the same code as you posted, except:

• I declared sumdig before calling it.
• I formatted the code properly.
• I defined sumdig with an explicit return type of int.
• I made it such that sumdig always returns sum, instead of having a control path that does not return a value despite the function being declared as returning an int.

Examining the logic, I'm reasonably certain that you will indeed get 15 as the output, since sum will be zero initialised. If you don't get this output, then the problem lies elsewhere, e.g., you are running a stale version of your program.

Originally Posted by coder1

static should not cause a problem because without it the whole program will not work as sum will always be initialized each time with the value we give and will not work as expected by the program

Well, it is true in this case because you are only calling sumdig once in main. As was mentioned to you earlier, once you call sumdig more than once, this use of a static local variable becomes problematic.

whiteflags' solution is one option, but I don't recommend it here. Rather, use what Salem suggested in post #4, which is what I suggested in post #11.

Originally Posted by coder1

But i have a question the return function will only works one time when "if" is false since for every true "if" recursion occurs like the "else" will do.so why we have to eliminate else as it will not matter in my opinion.

Firstly, a return statement is not a function. Now, the thing is that the return happens on each and every call to sumdig. If b != 0, control goes into the recursive call to sumdig, but after control leaves that recursive call, it reaches the return statement in the current call to sumdig.

edit: didn't read entire thread

Yeah, that looks correct, though I note that you're not coder1 and probably didn't need the practice