Why doesn't it work when I enter "NO"?
do{
printf("\n\nDo you wish to continue (yes or no): ");
uppercase(fgets(progress, sizeof progress, stdin));
fflush(stdin);
((strcmp(progress,"YES")!= 0 && strcmp(progress,"NO")!= 0)?printf("\nOnly 'yes' or 'no' will be accepted!\n"):printf("\n"));
}while(strcmp(progress,"YES")!= 0 && strcmp(progress,"NO")!= 0);at least some of your problem may be due to fgets( ) retains the newline character.
but im not sure how some of the other stuff you're doing would work... anyhow, I think you'll find it's best to try to keep code basic and readable for the next guy, rather than using clever logical constructions.
FWIW, my own style is that i don't like "do/while" loops when a simple "while" will suffice.
while (1)
{
printf("\nDo you wish to continue ('yes' or 'no'): ");
fgets(progress, sizeof progress, stdin);
fflush(stdin);
for (a=0; a<strlen(progress)-1; a++)
progress[a] = toupper(progress[a]);
progress[a] = 0;
if (!strcmp(progress,"YES") || !strcmp(progress,"NO"))
break;
printf("\nOnly 'yes' or 'no' will be accepted!\n");
}good point.
fflush is worthless in this. i should have removed it.
jephthah, "try to keep code basic and readable for the next guy, rather than using clever logical constructions" is very good advice. But then using if (!strcmp(progress,"YES") || !strcmp(progress,"NO")) is not easily understandable. It assumes you understand that strcmp() returns FALSE on equality, which is illogical. Better to use if ((strcmp(progress,"YES") == 0) || (strcmp(progress,"NO") == 0))
when i say "readable" i meant for the average programmer. not for someone who can't grasp that "!" is the same as "== 0 "
perhaps we should
#define YES_INDEED_THE_STRINGS_ARE_EQUAL 0?
when i say "readable" i meant for the average programmer. not for someone who can't grasp that "!" is the same as "== 0 "
perhaps we should
#define YES_INDEED_THE_STRINGS_ARE_EQUAL 0?
That works for me.
Programming is not just being able to put variables and operations together. There's a logic that you need to follow to be good. The thing I'm pointing out is a good programmer will not use a boolean test for a non-boolean comparison. strcmp() is not a boolean function, therefore it's bad form to treat it as such.
bah. fine, you can have it
:P
The problem was actually in my uppercase function. The length of the returning string was always +1 than what it should be or at the array limit depending on what the user entered. In my case if I entered "yes" in my char progress[4] array the length would be three + the null character but when I entered no the size of the modified array would be three, hence different from "NO" which is only two characters.
I settled with using a simple "y" for yes and "n" for no combined with the toupper() function in the ctype.h file.
Yes, that's exactly what i was trying to tell you in my first post.
fgets( ) returns the newline character, which is why you believed the the string was was always +1 from what you "thought" it should be.
because that's what fgets( ) does, according to the C programming language.
you need to change the newline into a NULL using the line of code i provided, or use strncmp( ) to ignore the newline.
otherwise your "fix" will never allow you to ever parse a string from stdin.
Hope I could help you...
instead of
strcmp
just use
strcmpi
for example
char a[5];
printf("\n\nDo you wish to continue yes or no): ");
if(strcmpi(a,"yes")==0{ printf("you choose YES");getch();}
else if(strcmpi(a,"no")==0{ printf("you choose NO");getch();}
else { printf("Invalid");getch();}
}
char a[5];
printf("\n\nDo you wish to continue yes or no): ");
if(strcmpi(a,"yes")==0{ printf("you choose YES");getch();}
else if(strcmpi(a,"no")==0{ printf("you choose NO");getch();}
else { printf("Invalid");getch();}
three problems with your post ^
(1) strcmpi is a Microsoft-specific implementation. it wont work on "real" C.
(2) strcmpi was deprecated as of 2005.
(3) your usage of getch( ) within the loops is irretrievably broken.
what on earth even makes you think that such a construct would work? have you ever written a program to get input from a terminal?
We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.