C Programming Language Exercise

Hey guys, I'm new to this forum and the C programming language. For some reason, I can't get this relatively simple program to print out the number of tabs, blanks and newlines I have in the input. Anybody have any ideas as to what's wrong?

Code:

#include "stdafx.h"
#include <stdio.h>

int _tmain(int argc, _TCHAR* argv[])
{
	int c=0;
	int nl=0;
	int b=0;
	int t=0;
	while((c=getchar())!=EOF){
		if (c== '\n')
			nl++;
		if (c==' ')
			b++;
		if (c=='\t')
			t++;
	}
	printf("Newlines = %d Blanks = %d Tabs = %d", nl,b,t);
}

int _tmain? Shouldn't that be int main?

Also, you're missing a return statement. Elysia or laserlight will come in and correct me but I think it may be an implicit return 0 by the C99 standard, but it's still good to have the return statement there anyway.

Worked for me, altho I removed "stdafx.h" and used int main():

Code:

[root~/C] ./a.out
asdagss
as		
	asdf[Ctrl-D]
Newlines = 3 Blanks = 2 Tabs = 3

The reason for the int _tmain and "stdafx.h" is because I copy pasted it directly from Visual C++, and that seems to be it's convention of setting up the code and precompiled headers. I might be doing something really stupid, but when the command prompt comes up and I put in say, a tab, the prompt just jumps a new line, expecting more input (without outputting anything). Any ideas?

I inserted the return 0; statement by the way, alas to no avail.

Originally Posted by serg_yegi

The reason for the int _tmain and "stdafx.h" is because I copy pasted it directly from Visual C++, and that seems to be it's convention of setting up the code and precompiled headers.

You copied it from what? Anyway, forget that. Just use:

Code:

int main(int argc, char *argv[])

without the wacky header.

Visual C++ is a GUI and compiler from Microsoft. I changed what you asked to no avail.

I know what Visual C++ is, I was kind of questioning the veracity of what you are saying (but since I don't use VS, I can't say any more).

Anyway: do you know how to signal EOF in the terminal? That's what the [Ctrl-D] indicated in my post. Witness, your loop will not end until then:

Code:

	while((c=getchar())!=EOF){

You could simplify by using:

Code:

while((c=getchar())!='Q'){

So this will end when a capital Q is encountered. However, the input will not get processed until you hit return after the Q.

VS likes to use unicode character sets. Changing the code to the following works with codeblocks 8.02 (mingw compiler).

Code:

#include <stdio.h>

int main(int argc, char* argv[])
{
	int c=0;
	int nl=0;
	int b=0;
	int t=0;
	while((c=getchar())!=EOF){
		if (c== '\n')
			nl++;
		if (c==' ')
			b++;
		if (c=='\t')
			t++;
	}
	printf("Newlines = %d Blanks = %d Tabs = %d", nl,b,t);
}

Better yet, write your code like this... (style points, ya know )

Code:

#include <stdio.h>
#include <conio.h>

int main(int argc, char* argv[])
{
	int c = 0;
	int nl = 0;
	int b = 0;
	int t = 0;
	
	do{
	        c = getchar();
		if (c == '\n')
			nl++;
		if (c == ' ')
			b++;
		if (c == '\t')
			t++;
	} while(c != EOF);
	
	printf("Newlines = %d Blanks = %d Tabs = %d", nl, b, t);
}

Ah, there you go. I in fact did not know how to signal EOF in the terminal. I used the ='Q' trick and the code worked fine, but how do I signal EOF exactly?

Okay, so _tmain is for wide char and unicode support.
http://www.coderjoe.net/archive/2007...ain-vs-_tmain/

Originally Posted by scwizzo

Better yet, write your code like this... (style points, ya know )

Since when is the long-winded do...while() better style than the more succinct while()?

Originally Posted by serg_yegi

Ah, there you go. I in fact did not know how to signal EOF in the terminal. I used the ='Q' trick and the code worked fine, but how do I signal EOF exactly?

I'm not sure what it is in windows; try ctrl-d or ctrl-z. You may or may not need to press return.

CTRL+D in *nix and CTRL+Z in Windows.

Strange, ctrl+z just seems to put ^Z into the command prompt and does nothing after I press return.

Try doing CTRL+Z twice.

Ah there you are. Ctrl- Z twice worked. Thanks a lot everyone for the help. Do I need to mark this thread resolved or something along those lines?