how to know the time taken to complete a program?

Originally Posted by Ganon11

Check out this function.

Originally Posted by Ganon11

Check out this function.

Originally Posted by RajuRaman

Actually i want to know the compilation time of a c++ program...could u pls tell me how can i use the function clock....

Originally Posted by r035198x

Some compilers are kind enough to tell you such details or maybe you are writing a C++ compiler using C++?

Originally Posted by RajuRaman

Ya I am writing a C++ program...and i tried the below program


#include<time.h>
#include<stdio.h>
#include<dos.h>
int main(void)
{
clock_t start , end;
start=clock();
delay(2000);
end= clock();
printf("the time was: %f \n",(end-start/CLK_TCK_;
return 0;
}

but this doesnt give the proper time..its giving the time after i press RUN..

Originally Posted by Banfa

What's your interest in knowing the compilation/link time?

The only times when it has ever been an issue in my carrier it has been acceptable to time it by hand using a trust wrist watch and just noting the approximate start and end times, i.e. normally people only care when the time is long enough to measure inaccurately with knowing the exact start and stop times.

Originally Posted by Banfa

What's your interest in knowing the compilation/link time?

The only times when it has ever been an issue in my carrier it has been acceptable to time it by hand using a trust wrist watch and just noting the approximate start and end times, i.e. normally people only care when the time is long enough to measure inaccurately with knowing the exact start and stop times.

Originally Posted by r035198x

I'm of the opinion that writing a C++ compiler is actually useless in itself so there.

Originally Posted by RajuRaman

My interest is that..I hav 2 C++ programs....and I want to know which one will take less time...and choose the best between the two...and the time is in milli seconds..which cannot b noted using a wrist watch..

Originally Posted by Banfa

That rather depends on if you are manufacturing a new processor or not. If you are creating a new processor then not creating a compiler for it is going to somewhat limit it's use :D

Originally Posted by r035198x

A fast program is not a program that takes a short time to compile. It is one that takes a short time to run.

Originally Posted by Banfa

Actually almost certainly the reverse, optimisation takes far longer than actual compilation of the code so if you where to switch off the optimisation in your compiler you will almost certainly end up with a program that compiles faster.

However optimised code almost always runs faster than un-optimised code so if you switch off the optimiser you will almost certainly end up with a program that runs slower.

Originally Posted by r035198x

So how is my comment the reverse of this?