i get this error "solution.c:9:4: warning: implicit declaration of function 'stricmp' [-Wimplicit-function-declaration] x= stricmp(ap,c);"

Question

 #include<stdio.h>
 #include<stdlib.h>
 #include<string.h>
 #include<time.h>
 int main()
 {
             int hh,mm,ss;
             char ap[2];
             scanf("%d%d%d%s",&hh,&mm,&ss,ap);
             if(stricmp(ap,"AM")!=0)
             {
                   hh+=12;

              }
              printf("%d:%d:%d",hh,mm,ss);
              return 0;
            ##

This code converts a 12 hour clock format to 24 hour clock format

##}

Aside: `char ap[2];` is too short. It cannot hold the nul-terminated string `"AM"`. — Weather Vane, Mar 25 '16 at 12:07
Thank you for your comment.So in strings ,1 extra memory location is alloted for null character right as strings are appended with '/0' — nishchalpro, Mar 25 '16 at 12:12
That's right, and if you type in `am` to satisfy the `%s` format writing to `ap[2]` you'll cause a buffer overflow. — Weather Vane, Mar 25 '16 at 12:17
[`stricmp`](http://stackoverflow.com/a/1784777/1212012) is not standard. Use [`strcasecmp`](http://linux.die.net/man/3/strcasecmp) on linux or [`_stricmp`](https://msdn.microsoft.com/fr-fr/library/k59z8dwe.aspx) on windows — Mathieu, Mar 25 '16 at 12:17
It is best to implement `stricmp` on your own, for maximum portability. — lost_in_the_source, Mar 25 '16 at 12:27
@nishchalpro sorry: that was why it was posted as an "Aside" comment, not an answer. — Weather Vane, Mar 25 '16 at 12:28
@purplepsycho thank you for commenting.......i tried strcasecmp and it solved my problem thanks a lot!! — nishchalpro, Mar 25 '16 at 12:29
@stackptr can you ellaborate if you have time n if you dont mind — nishchalpro, Mar 25 '16 at 12:32
Write stricmp yourself. That is, `int stricmp(const char *a, const char *b) { ... }`. Instead of the ellipsis, put your implementation there — lost_in_the_source, Mar 25 '16 at 12:32
left to you,write it if you feel it might help others...of course it helped me@stackptr — nishchalpro, Mar 25 '16 at 12:36

score 0 · Accepted Answer · edited May 23 '17 at 12:31

Insufficient string space. Also add limit to scanning

char ap[3];
scanf("%d%d%d%2s",&hh,&mm,&ss,ap);

stricmp is not standard. Use strcasecmp on linux or _stricmp on windows.

Functionally missing the handling of times like 12 34 56 AM which should change to 0 34 56.

if(stricmp(ap,"AM")==0) {
  if (hh >= 12) hh -= 12;
} else if(stricmp(ap,"PM")==0) {
  hh +-= 12;
}

More usual to print minutes.seconds with leading zeros.

printf("%d:%02d:%02d",hh,mm,ss);

i get this error "solution.c:9:4: warning: implicit declaration of function 'stricmp' [-Wimplicit-function-declaration] x= stricmp(ap,c);"

This code converts a 12 hour clock format to 24 hour clock format

1 Answers1