c++

[bob]

If you have this:

int c;

Which is faster?

a. c = c + 1;

b. c++;

 

[Bo Persson]

(e-mail address removed) wrote:
:: If you have this:
::
:: int c;
::
:: Which is faster?
::
:: a. c = c + 1;
::
:: b. c++;

No difference.

 

[jkherciueh]

If you have this:

int c;

Which is faster?

a. c = c + 1;

b. c++;

Depends on hardware, compiler, compiler settings and options, and possibly
the day of the week. Your only option to get a reliable answer is to
measure. That said, chances are that your compiler will generate identical
object code for both statements.


Best

Kai-Uwe Bux

 

[Victor Bazarov]

If you have this:

int c;

Which is faster?

a. c = c + 1;

b. c++;

None. Without a doubt, it's

c. ++c;

V

 

[Ron Natalie]

None. Without a doubt, it's

c. ++c;

V

I have doubts.

 

[James Kanze]

None. Without a doubt, it's

c. ++c;

Sorry Victor, but that's false. Every compiler I've ever used
generates exactly the same code for all three.

More generally, the answer to almost any question "which is
faster" is: it depends on the compiler. You have to set up a
test harness and measure. (In particular: despite claims by
some prominent "experts", I've yet to find a case where there
was a measurable difference between c++ and ++c, regardless of
the type of c. I can easily create cases where ++c would be
significantly faster, but they don't seem to actually occur in
real life.)

 

[Victor Bazarov]

None. Without a doubt, it's

c. ++c;

Sorry Victor, but that's false. [..]

Sorry, *what* is false? "None"?

Lighten up, James. Happy New Year!

V

 

[James Kanze]

(e-mail address removed) wrote:
If you have this:
int c;
Which is faster?
a. c = c + 1;
b. c++;
None. Without a doubt, it's
c. ++c;

Sorry Victor, but that's false. [..]

Sorry, *what* is false? "None"?

That ++c is faster than the others.