C/C++ Beginner's Guide and Post Basic Questions here

[nims11]

[/COLOR]Output Problem

cout<<a++<<a++<<b--<<--b<<++b<<--b;

I m havin problem in assumin the ouput of such syntax. Usullly i get unexpected results. Any reason for tht and way to encounter it?

let a=1 and b=2 before this 'cout' statement.
then here is what happens when "cout<<a++<<a++<<b--<<--b<<++b<<--b;" is executed.

a++
output a; a+=1;
a is now 2, b is now 2;
output status : 1

a++
output a; a+=1;
a is now 3, b is now 2;
output status : 12

b--
output b; b-=1;
a is now 3, b is now 1;
output status : 122

--b
b-=1;output b;
a is now 3, b is now 0;
output status : 1220

++b
b+=1;output b;
a is now 3, b is now 1;
output status : 12201

--b
b-=1;output b;
a is now 3, b is now -1;
output status : 122010


Final Output- 122010.

 

[Neuron]

^^It depends on the compiler IMO.

 

[Liverpool_fan]

^^It depends on the compiler IMO.

This. It falls under the domain what we call "Undefined Behaviour".

Ron: Try compiling your C++ code with g++ -Wall flag and see the warning.

As for global variables.
c++ - Are global variables bad? - Stack Overflow
Global Variables Are Bad

 

[mitraark]

Any software all in one package i can use to write and compile C [ GCC ] >?? DevC++ or something ??? Something which can be installed on machines without Internet connection [ unlike MinGW which is downloading files ]

---------- Post added at 04:01 PM ---------- Previous post was at 03:49 PM ----------

MinGW is working great , will i be able to install it in Windows 7 6 Bit PC without Internet connection ?

 

[vickybat]

Devc++ is the best imo.

 

[ico]

I am a student and can't understand why the author of this post is telling us not to use turbo C++ thats the compiler they teach us in school and college

Let me put this straightforwardly. Indians are idiots. Not even Pakistanis use Turbo C++.

Teachers are not willing to move on. The curriculum makers are sleeping. et cetera.

---------- Post added at 05:07 PM ---------- Previous post was at 05:03 PM ----------

Any software all in one package i can use to write and compile C [ GCC ] >?? DevC++ or something ??? Something which can be installed on machines without Internet connection [ unlike MinGW which is downloading files ]

---------- Post added at 04:01 PM ---------- Previous post was at 03:49 PM ----------

MinGW is working great , will i be able to install it in Windows 7 6 Bit PC without Internet connection ?

Try this out: CodeLite IDE LiteEditor/Download

Here is the direct link: *sourceforge.net/projects/codelite/...9/codelite-2.9.0.4684-mingw4.4.1.exe/download

 

[vickybat]

^^ Good point made ico.We should move on. But ain't devc++ suffice?

 

[ico]

^^ Good point made ico.We should move on. But ain't devc++ suffice?

It will easily suffice but Dev C++ has not seen any development since 6 years.

 

[vickybat]

^^Okay, so whats widely used in development now?

 

[ico]

^^Okay, so whats widely used in development now?

Anything with which you are comfortable with.

Eclipse, Netbeans and Microsoft Visual C++ are excellent. But many of their features are unnecessary if you are only into basic programming.

Dev C++ comes with an old version of MiniGW by default.

 

[vickybat]

^^ eclipse and netbeans are for java only right. I'm interested only in c++. So Microsoft Visual C++ will be a good choice right?

 

[ico]

No, you can use Netbeans and Eclipse for C/C++ programming too. Microsoft Visual C++ is a good choice, no doubt.

 

[vickybat]

^^ Thanks for that info ico.

 

[azaad_shri75]

^ you can use qt also.........

 

[nims11]

Hey guyz i have a problem...
There is an easy question at SPOJ whose answer is a set of many numbers which i have to output to stdout. the time limit is 6 sec. i used C++. The algo does the processing of these numbers in less than 2 seconds in worst case. But outputting these numbers is causing the program to exceed the time limit!! any suggestions?

 

[Neuron]

Instead of printing each of the number with separate output commands,use a single command to output a group of numbers at the same time.

Run following codes,the second one will be faster.

for(i=0;i<100000;i++)
printf("%d ",i);

for(i=0,j=1,k=2;i<100000;i+=3,j+=3,k+=3)
printf(" %d %d %d",i,j,k);

 

[nims11]

sorry for replying late...
thanx it works but i had to use a series of 10 "%d" to make it significantly faster...

Most confusing C Code.... - Fun Enclave

 

[Neuron]

^^Wow,great find.

 

[RBX]

Re: Post your C/C++ Programs Here

How will this be evaluated in C and C++ ?

printf("%d",sizeof('A'));

 

[arpanmukherjee1]

Re: Post your C/C++ Programs Here

Code:

#include <STDIO.H>  
 using namespace std;   
int main(char *args, int argc) 
{ 
  printf("%d float\n",sizeof(float));  
  printf("%d int\n",sizeof(int)); 
  printf("%d char\n",sizeof(char));  
  printf("%d long\n",sizeof(long));  
  return 0; 
} 

Output:

4 float
4 int
1 char  //your answer
4 long