I can't get my program to loop properly. Here's the code:
#include <stdio.h>
main()
{
char a;
printf("Enter a letter\n");
for ( ; ; )
scanf("%c",&a);
printf("\nThe decimal value of the character you entered is %d\n\n",a);
}
What am I doing wrong?
looping
I can't get my program to loop properly. Here's the code:
#include <stdio.h>
main()
{
char a;
printf("Enter a letter\n");
for ( ; ; )
scanf("%c",&a);
printf("\nThe decimal value of the character you entered is %d\n\n",a);
}
What am I doing wrong?
Perhaps something more like this is what you want:
Multiline loops must be surrounded by a block.Code:#include <stdio.h> int main(void) { char a; printf("Enter a letter\n"); for ( ; ; ) { scanf("%c%*c",&a); printf("\nThe decimal value of the character you entered is %d\n\n",a); } return 0; }
-Prelude
My best code is written with the delete key.
i dont want to hijack this thread but i always wondered what
that
statement actually does.Code:for ( ; ; )
anyone?
thanks
it's an infinate loop. you can leave out any of the paremetes(?) of a for statement.. if you have nothing to stop the loop (the second paremeter) then it never stops.. putting the other two in is then pointless, so you do for( ; ; ) for an infinate loop.
If I had a world of my own, everything would be nonsense. Nothing would be what it is, because everything would be what it isn't. And contrariwise, what it is, it wouldn't be, and what it wouldn't be, it would. You see?
>anyone?
It's an infinite loop, there's no condition to stop it and no need for initialization or modification of a counter.
-Prelude
My best code is written with the delete key.
Why does the scanf statement have to be scanf("%c%*c",&a); instead of scanf("%c",&a);?
>Why does the scanf statement have to be scanf("%c%*c",&a); instead of scanf("%c",&a);?
Because otherwise you'll loop twice for each letter, once for the letter and once for the return key. The %*c flag tells scanf to read a single character and discard it. Since we know it's the return key we can safely get rid of it for the sake of pretty output.
-Prelude
My best code is written with the delete key.
Yes, but the real question is: which is better? while(1) or for( ; ; )? I'm sure there will be a huge debate about this on the General Discussions board.Originally posted by MadHatter
it's an infinate loop. you can leave out any of the paremetes(?) of a for statement.. if you have nothing to stop the loop (the second paremeter) then it never stops.. putting the other two in is then pointless, so you do for( ; ; ) for an infinate loop.
for(; ; ) = We haven't any condition here, so I don't think that the computer every time check the condition.Yes, but the real question is: which is better? while(1) or for( ; ; )? I'm sure there will be a huge debate about this on the General Discussions board.
while(1) = We have a condition here, so the computer will check always the condition (or not?).
I really don't no if in this case:
The computer check any condition....Code:for(; ; ) { printf("Blah"); printf("\nBleh"); a = b*b; }
He just jump to the start, right?
I don't think that for(; ; ) is better than while(1) and vice-versa.
while(1) is 8 letters
for( ; ; ) is 7 letters...
"Can i really learn this? If i cant, why bother?"
I think that it takes around a nanosecond shorter for me to understand what while(TRUE) is doing, than for(;so I use the while statement. It look better too.
You had to hit 10 keys to write for( ; ; ) and only 8 to write while(1)Originally posted by C-learning
while(1) is 8 letters
for( ; ; ) is 7 letters...
Thats true.
But i was never good at math...
"Can i really learn this? If i cant, why bother?"
>which is better? while(1) or for( ; ; )?
It's a matter of preference, but
while ( 1 )
will often cause a warning about a constant loop condition while
for ( ; ; )
doesn't have this problem.
-Prelude
My best code is written with the delete key.
you forgot the SHIFTYou had to hit 10 keys to write for( ; ; ) and only 8 to write while(1)
Look, you had to hit 12 keys hehe
SHIFT+9= (
SHIFT+0 = )
Enough of the pointless comments. If you want this thread reopened, PM me or another mod...
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