How can I cast while doing a division assignment?

Question

I am practicing C basics for my exam and encountered a tricky situation while doing a simple for loop:

int main()
{
    for( double i = 9.999; i > 0; )
    {
        printf("%d ", ((int)i) /= 2);
    }

    return 0;
}

I get an error:

error: lvalue required as left operand of assignment
         printf("%d ", ((int)i) /= 2);
                                ^~

Isn't (int)i an lvalue? Or how could you rewrite it to get the output: 4 2 1 0?

Answer 1

Isn't (int)i an lvalue ?

i is, (int)i isn't.

Or how could you rewrite it to get the output: 4 2 1 0?

The best you can do is be clear and separate the statements:

i = (int)i / 2;
printf("%d ", (int)i);

Note that you cannot use i /= 2 in the first one since then you will not get to zero quickly by truncating.