Re: Bitwise operators

On 19 Giu, 11:32, Richard Heathfield <r...@xxxxxxxxxxxxxxx> wrote:
den2k said:
Given subtraction, division becomes not only possible but even easy.
Consider 34 / 10 (which we need to do if we're going to get the result 3
and remainder 4). 34 is 100010 in binary, and ten is 1010. Observe long
division in binary, noting that subtraction is done with ^ & << and the
two's complement, comparison can be done by subtraction, isolating the
bits necessary for the trial divisions can be done using shift and AND,
and "bringing down a bit" can be done with shift and OR:

1010)100010
1010 <---- Subtrahend <= minuend? No.

_0000
1010)100010
1010 <---- Subtrahend <= minuend? Yes. Subtract.

_00001
1010)100010
1010
---
111 <----- bring down a bit

_00001
1010)100010
1010
---
1110
1010 <---- Subtrahend <= minuend? Yes. Subtract.

_000011 <---- Result: 3
1010)100010
1010
---
1110
1010
---
100 <---- Remainder: 4

Yes, Virginia, you *can* divide by ten, even if you're thinking in binary.


Whoops I unconsciously thougt to a sigle bitwise operator.. and I
didn't know so well the use of bitwise Operators in order to do the
basilar operations. Thanks a lot.
.

Relevant Pages

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