Thread: Strange effect of braces (K&R chap 1)

Hi,

I've read that extra braces won't have an effect on compiling code, but when I ran a piece of code through my compiler in Ubuntu with an extra set of braces (it's a step toward completing an example from K&R, 1.17), the program seemed to repeat itself several times over.

I've experimented removing them and adding them and it always has the same effect of making the code run several times. Any idea what could be happening?

EDIT: here is the code

A - Working normally

Code:

#include <stdio.h>

#define IN 1
#define OUT 0
#define MAXLINE 100
#define MAXWORD 100

main()
{
	int i, x, c, b, nline, nword, state, pass;
	int wdcount[MAXWORD];
	state = OUT;
	i = x = nline = nword = 0;
	while ((c = getchar())!= EOF) {
		if (c != '\n'){
			if (c != '\t' && c != ' ' && state == OUT){
			++nword;
			state = IN;
			}
			else if (c != '\t' && c != ' ' && state == IN){
			;
			}			
			else if (c == '\t' || c == ' ' && state == IN){
			state = OUT;
			}
			else if (c == '\t' || c == ' ' && state == IN){
			;
			}
			}
		
		
		else if (c == '\n'){
			wdcount[i] = nword;
			nword=0;
			++i;
			state = OUT;
			}

		
			}
			
		for (x = 0; x <i;++x){
		printf("%d\n", wdcount[x]);
			}
		printf("Yankee\n");
	}

B - Extra Braces before if, at end of printf;

Code:

#include <stdio.h>

#define IN 1
#define OUT 0
#define MAXLINE 100
#define MAXWORD 100

main()
{
	int i, x, c, b, nline, nword, state, pass;
	int wdcount[MAXWORD];
	state = OUT;
	i = x = nline = nword = 0;
	while ((c = getchar())!= EOF) {
		{if (c != '\n'){
			if (c != '\t' && c != ' ' && state == OUT){
			++nword;
			state = IN;
			}
			else if (c != '\t' && c != ' ' && state == IN){
			;
			}			
			else if (c == '\t' || c == ' ' && state == IN){
			state = OUT;
			}
			else if (c == '\t' || c == ' ' && state == IN){
			;
			}
			}
		
		
		else if (c == '\n'){
			wdcount[i] = nword;
			nword=0;
			++i;
			state = OUT;
			}

		
			}
			
		for (x = 0; x <i;++x){
		printf("%d\n", wdcount[x]);
			}
		printf("Yankee\n");}
	}

Of course braces have an effect.

Code:

if( a == b )
    this();
notthis();

Compared to:

Code:

if( a == b )
{
    this();
    andthis();
}

Without seeing what you are actually doing, and without a better explanation on your part, all we can do is make wild guesses. Normally I'd use my ESP to see what it is you are doing over there, but I haven't had my coffee yet.


Quzah.

Your indenting style is also going to make things more difficult for you, and others who study your code.

If you are indenting some dependent lines of code, but leaving others such lines of code not indented, it's just that much more work to understand your code.

Why do this?

Code:

while(someTestHere) {
   if(anotherTestHere) {   //an indented dependent line of code - Good!
   actionToTakeIfAnotherTestIsTrue; //an unindented dependent line of code. Poor Style.
   }
}

//When this is so much clearer:
while(someTestHere) {
   if(anotherTestHere) {   //an indented dependent line of code - Good!
      actionToTakeIfAnotherTestIsTrue; //an indented dependent line of code. 
   }
}

As you code more, your eye becomes trained to catch irregularities in your code . If you use a very consistent style of indenting dependent lines of code, then your coding will improve, and others will understand it easier.