/prog/ - SWAP — World4ch

Name: Anonymous 2011-10-17 15:25



#define SWAP(a, b) ((&(a) == &(b)) || \

                    (((a) -= (b)), ((b) += (a)), ((a) = (b) - (a))))

ENTERPRISE SWAPPING

inb4 overflow

Name: Anonymous 2011-10-17 17:08

overflow wraps around anyway

Name: Anonymous 2011-10-17 17:37



#define SWAP(a,b,c)  c = a;\

                     a = b;\

                     a = c

Name: Anonymous 2011-10-17 17:43

>>3
This is a masterpiece.

Name: Anonymous 2011-10-17 17:49

>>1
floating point precision

Name: Anonymous 2011-10-17 18:31

>>3
What a bloat

Name: Anonymous 2011-10-17 20:02

Jesus, that's clever, >>1.
Show more of your work!

|10/10|

Name: Anonymous 2011-10-17 20:31

>>7
Let x,y,m be integers

Maximum Function:
m = x ^ ((x ^ y) & -(x < y));
where r ends up as the maximum of x and y

Minimum Function:
m = y ^ ((x ^ y) & -(x < y));
where r ends up as the minimum of x and y

Name: swagger 2011-10-17 21:05

#define SWAG(a, b) ((&(a) == &(b)) || \
(((a) -= (b)), ((b) += (a)), ((a) = (b) - (a))))

Name: Anonymous 2011-10-17 21:10

>>9
not enough!

#define SWAG(a, b) do((&(a) == &(b)) || \

                    (((a) -= (b)), ((b) += (a)), ((a) = (b) - (a))))while(0)

Name: Anonymous 2011-10-17 21:23

>>10
guess I got my swagger back

Name: Anonymous 2011-10-17 22:17

That's really clever, and it's cool to see, but xor swap is probably faster, seeing how the xor operation is simpler to do than addition (at least I as a human being could do an xor a lot faster than an addition. I don't know about how intense modern architectures are...)



#define eXchange(a, b) do{(&(a) == &(b)) ||    \

                           ((a) ^= (b),        \

                            (b) ^= (a),        \

                            (a) ^= (b))}while(0)

Name: Anonymous 2011-10-17 23:32

>>11
TRUTH
NEW WATCH ALERT

Name: Anonymous 2011-10-17 23:54



 mov eax, [a]

 xchg eax, [b]

SWAP

1 Name: Anonymous 2011-10-17 15:25

2 Name: Anonymous 2011-10-17 17:08

3 Name: Anonymous 2011-10-17 17:37

4 Name: Anonymous 2011-10-17 17:43

5 Name: Anonymous 2011-10-17 17:49

6 Name: Anonymous 2011-10-17 18:31

7 Name: Anonymous 2011-10-17 20:02

8 Name: Anonymous 2011-10-17 20:31

9 Name: swagger 2011-10-17 21:05

10 Name: Anonymous 2011-10-17 21:10

11 Name: Anonymous 2011-10-17 21:23

12 Name: Anonymous 2011-10-17 22:17

13 Name: Anonymous 2011-10-17 23:32

14 Name: Anonymous 2011-10-17 23:54