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COMPILER IGNORING ++

May 3, 2015 at 7:43pm
SYOB SYOT (7)
HAY PROGRAMMERS,

I HAVE A PROBLEM WITH VISUAL STUDIO 2013 C++ CODE.

I HAVE THIS CODE:
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#include <stdio.h>
__int8 a;
__int8 b=0;
void main(void)
{
	for (int i=0; i < 6; i++)
	{
		scanf("%ld", &a);
		printf("b is equal to: %ld", b);
		b++;
	}
}
Edit & run on cpp.sh


THIS CODE COMPILES WITHOUT ERRORS.
WHAT THIS DOES IS THAT IT CREATES INTEGER VARIABLE WHICH IS 8 BITS LONG, ASKS USER TO ENTER A NUMBER IN THAT VARIABLE SIX TIMES. (NO POINT OF DOING THIS SIX TIMES, BUT IGNORE THIS FOR NOW).
ALSO, IT HAS A 8 BIT INTEGER VARIABLE WHICH COUNTS THE NUMBER OF TIMES USER ENTERED A NUMBER.
BUT THE PROBLEM IS THAT FOR SOME REASON COMPILER IGNORES b++; LINE.

OUTPUT FROM THIS CODE IS:
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b is equal to: 0
b is equal to: 0
b is equal to: 0
b is equal to: 0
b is equal to: 0
b is equal to: 0


WHY?
I TYPED b++; AND IT SHOULD BE GRATER IN EVERY ITTERATION.

WHAT IS ODD IS THAT IF I REMOVE scanf FUNCTION OUTPUT IS:
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b is equal to: 0
b is equal to: 1
b is equal to: 2
b is equal to: 3
b is equal to: 4
b is equal to: 5

ALSO, IF I DECLARE b AS __int16 AND NOT __int8 IT WORKS CORRECT WITH OR WITHOUT scanf.
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b is equal to: 0
b is equal to: 1
b is equal to: 2
b is equal to: 3
b is equal to: 4
b is equal to: 5


WHY b CAN NOT BE DECLARED AS __int8 IN THIS LOOP?
OR WHY IS scanf CAUSEING COMPILER TO IGNORE b++ COMMAND?

THANX
Last edited on May 3, 2015 at 7:43pm
May 3, 2015 at 7:52pm
AbstractionAnon (6954)
You're lucky that's not blowing up.

In line 8, you're telling scanf that a is a long int (%ld) which is typically 32 bits. scanf will obligingly store 32 bits into a (an 8 bit number) and whatever follows it on the stack.
May 3, 2015 at 8:32pm
SYOB SYOT (7)
THANX MAN!
THIS WAS THE PROBLEM.
I THOUGHTH THAT l IS PREFIX FOR SHORTEST VARIABLES (l LIKE LOWEST (SIZE) OR SOMETHING LIKE THIS).


I USE %c NOW.
IT STILL DID NOT WORK CORRECT AT THE BEGGINING BECAUSE IT WAS SKIPPING SCANF IN EVERY SECOND ITERATION, BUT, I FOUND OUT THAT I NEED TO FLUSH BUFFER, AND NOW IT WORKS GREAT.

I WOULD NEWER FIGURE IT OUT WITHOUT YOU. I REALLY THOUGHT THAT ld STANDS FOR LOWEST INT, THAT IS INT WITH LOWEST (SMALLEST) SIZE.
THANX!
BYE
May 3, 2015 at 8:38pm
chouhaizi (39)
I'm deaf... Megaphone not needed...
May 31, 2015 at 5:21pm
SYOB SYOT (7)
NO, I AM JUST USING STANDARD COMMANDS, THERE IS NO COMMAND NAMED "MEGAPHONE" FOUND IN THE FILE.
May 31, 2015 at 5:29pm
rlc4 (32)
Here, let me translate what chouhaizi said:
"Stop yelling!"
May 31, 2015 at 10:46pm
SYOB SYOT (7)
I AM NOT YELLING. ;)
I AM WERY CALM AND HAPPY RIGHT NOW. :P
I WOULD NEVER YELL ON YOU. ;) ☺☺
Jun 1, 2015 at 12:40am
rlc4 (32)
All Caps = Yelling on the Internet.
And why would you ever yell on somebody?

Good day...
Jun 1, 2015 at 12:53am
IEatDingos (2)
Just speak normally or else your next thread that you will probably post in 60 seconds will not get any help.
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