Thread: String Justifying

Hello people,

I'm trying make right-justify the strings entered,
User enters different size of strings and I'm calculating their length and find the maximum of them...
For instance

First Input
-->str
Second Input
-->strin
Third
-->string

as partial What I've done is below

Code:

s_max=strlen(string[0].surname);
for(i=0;i<3;i++){
	s_size = strlen(string[i].surname);
	if( s_size > s_max){
		s_max=(strlen(string[i].surname));
	}
}


i=0;
do{
	printf("%s\n",string[i].surname);//it's the part that I cant solve
	i++;
	
}while(i!=3);
	
	return 0;
}

the code above is a part of main func.,
I want to print strings as Right Aligned and as I'm doing this, I want to use reference the longest string ,i.e. printf("%6s\n",...) printf("%Ns",...)

What I cant do is that after I found the the longest string's length in for loop, how can I use that value while printing??
%x s if s_max is 7 it's gonna bi %7s....

You can use a star as a placeholder for a run time field width:

Code:

printf( "%*s\n", width, string );

Originally Posted by Noir

You can use a star as a placeholder for a run time field width:

Code:

printf( "%*s\n", width, string );

Thanks noir, I coded excatly what you've written above and it works fine ...

Sometimes it can be tough to reach this kind of information, because in beginner and regular C books does not contain such information, i.e. sams teach ur self C, I've had a look but couldnt find anything about this type tuning in issues..

It can be helpful to supplement your instructional text with a IDEs help files or the man pages.

Originally Posted by citizen

It can be helpful to supplement your instructional text with a IDEs help files or the man pages.

what do you mean by saying IDEs help files or man pages?

man pages are help documentation for command line operating systems such as unix or linux. Since these operating systems come with compilers, it makes sence that there is also documentation that explains what certain functions do, what's declared in some standard header, et cetera. That's what compilers or integraded development environments come bundled with. Of course, you could always search for online documentation, like here, or try using any good search engine.

You can easily solve this with a bit of arithmetic. Say the longest possible width is 10 char's wide, and you want something right justified. (Note that printf() has it's own justification parameter - but we're talking here about a do-it-yourself approach).
So you subtract the number of char's (digits or letters) from that 10 and now you know how many tiimes you need to first print a space BEFORE you print your string, to make it perfectly right justified.

Say your string is 6 char's wide: 10 - 6 equals 4, so:

Code:

for (i = 0; i < 4; i++)
    putchar(' ');

or more generically:
spaces = 10 - (strlen(yourString));
for (i = 0; i < spaces; i ++) 
   putchar(' ');  /* or putchar(32);

Just another way to solve the problem.

Adak

Originally Posted by citizen

man pages are help documentation for command line operating systems such as unix or linux. Since these operating systems come with compilers, it makes sence that there is also documentation that explains what certain functions do, what's declared in some standard header, et cetera. That's what compilers or integraded development environments come bundled with. Of course, you could always search for online documentation, like here, or try using any good search engine.

Thanks for the explanation and I've had a look the site you suggested first, and looks like another world to me : ) but it must be really helpful for advanced implementations.

Originally Posted by Adak

You can easily solve this with a bit of arithmetic. Say the longest possible width is 10 char's wide, and you want something right justified. (Note that printf() has it's own justification parameter - but we're talking here about a do-it-yourself approach).
So you subtract the number of char's (digits or letters) from that 10 and now you know how many tiimes you need to first print a space BEFORE you print your string, to make it perfectly right justified.

Say your string is 6 char's wide: 10 - 6 equals 4, so:

Code:

for (i = 0; i < 4; i++)
    putchar(' ');

or more generically:
spaces = 10 - (strlen(yourString));
for (i = 0; i < spaces; i ++) 
   putchar(' ');  /* or putchar(32);

Just another way to solve the problem.

Adak

All I can say is , it's cool Though for a beginner programmer it's a bit hard to think of this way, it must be what the programming is .

Originally Posted by Adak

I haven't taken the time to read through your other responses, but you DO know that, of course, printf() has a left and right justification flag, right?

Naturally.

Letters are left-justified, numbers right justified, by default, but that can be overridden.

Try this:

Code:

int i = 2;
char msg = {I want this right justified!\0};
printf("\n%+2s %d", msg, i);

Excuse me, but I thought you already knew this or had received this answer from another poster already, and your instructor wanted you to do it "old school" style.

Adak

Actually, I didnt know this, I mean printf("\n%+2s %d", msg, i); this part looks like a bit weird to me,and I've just compiled it and doesnt make any sense, maybe I just made something wrong.

And yes I'm instructed to do it damn old school sytle, but I hate this..So far What I've understood from programming is that there's always second ways to do something, but old school type of programming makes you stop thinking or acting freely or more creative...

From this kind of board and these people I've learned much more things than what I learned from instructors...

Hey M0ntana, make it "%+42s, %d", not just %+2!!

You'd have a heck of a hard time writing a 29 char string in a field just 2 char's long!

Adak

Originally Posted by Adak

Hey M0ntana, make it "%+42s, %d", not just %+2!!

You'd have a heck of a hard time writing a 29 char string in a field just 2 char's long!

Adak

Code:

int i = 2;
char *msg = {"I want this right justified!\n" };
printf("\n%+50s %d", msg, i);}

it works fine, obviusly I had tried it by puttin 14 but I didn't calculate the excat length of string as 29, that's why it didnt make any sense

By the way , I said it looks like weird in my post above, because of "+" that you put in printf(),
I just realized the both gives the same result (syntaxly same)
&+50s and %50s, I put "-" but it doesnt return with any change...
anyway thanks again, these things'r really fun