Consecutive function call problem

[Tafhim]

I've defined one function and am taking 2 values off it by calling it 2 times. Like this:

count1=counter(subject1);
couunt2=counter(subject2);

But the problem is that the process is being run only once.

But if I modify the code like this:

count1=counter(subject1);
cout << count1 << endl;
count2=counter(subject2);

Then the process is ok. This is also true for cout << ""; in the place of the previous cout.

I can't seem to understand what is really going on.

#include <iostream.h>
int digits(long long);
int main()
{
    long long num1, num2;

    while(cin >> num1 >> num2)
    {
        int lnm1, lnm2;

        lnm2=digits(num2);
        cout << "";
        lnm1=digits(num1);
    }
    return 0;
}

int digits(long long n)
{
    int i, j, rem;

    for (i=10, j=1 ; rem>=0 ; i*=10, j++)
    {
        rem=n-i;
        cout << "rem for " << n << "=" << rem << endl;
    }

    return j-1;
}

[b]EDIT::::::::[/B]
Later I did something this

#include <iostream.h>
int digits(long long);
int main()
{
    long long num1, num2;

    while(cin >> num1 >> num2)
    {

	int lnm1;
	lnm1=digits(num1);
	//cout << lnm1 << endl;

	int lnm2;
	lnm2=digits(num2);
	//cout << lnm2 << endl;
    }
    return 0;
}

int digits(long long n)
{
    int i, j, rem;

    for (i=10, j=1 ; rem>=0 ; i*=10, j++)
    {
	rem=n-i;
	cout << "rem for " << n << "=" << rem << endl;
    }

    return j-1;
}

This is now working correctly but my question is why can't it be like the first one?

[kbw]

In function digits, rem, which is used to control the loop, is uninitialised.

[Tafhim]

Thanks "kbw". Your opinion was right. But just to make things clear for myself, why does work the way I said it did. I mean:

int lnm1;
{function call}
int lnm2;
{function call}

Why does it work this way? When the rem is uninitialized?

[kbw]

cout << count1 << endl; is a series of function calls that use the stack. They could leave some value in the memory location that rem eventually occupies, making it take a different value between calls.

It's most likely zero the first time and non-zero the second time.