Re: [Dev-C++] Decrementing for loop problem

[Per W. <pw...@ia...>]

Note that it is easier to do direct bit manipulations using the shift
operator.

unsigned char val = 0x25; // number to print
mask = 0x80; // start from most significant bit
while (mask) {
    printf("%d",(val & mask) != 0);
    mask >>= 1;
}


Also don't forget that checking a specific bit in a number is just:
    if (num & (1 << bitpos)) {
        ...
    }

Setting the bit is:
    num  |= 1 << bitpos;

Clearing it is:
    num &= ~(1 << bitpos);

/Per W

On Sat, 16 Jul 2005, Roger Furer wrote:

> Aloha from Honolulu,
>     I have a little c program for studying bit operators.  I'm trying to
> print out a byte in binary form.  My first 'for' loop increments the
> index 'i' and works fine, but the number reads backwards.  I tried the
> same thing but with an index that is decremented 'x--', but the loop
> never executes.  Can anyone help?
> Here is the program: