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sg001

macrumors newbie
Original poster
Jul 30, 2012
9
0
Code:
#include <stdio.h>

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

#define SEC_PER_MIN 60
#define MIN_PER_HOUR 60
#define ERROR_MSG "Format must be HHMMSS"

int sec, min, hour;

   printf("Enter 24 hour time in HHMMSS format:\n");
   scanf("%d %d %d", &hour, &min, &sec);
   
   if (hour>23 || min>59 || sec>59){
   printf("No such time\n");
   }
   if (hour<0 || min<0 || sec<0){
      printf("No such time");
   }
   else {
      printf("The time is %d:%d:%d\n",hour, min, sec);
   }
   return 0;
For some reason when the program prompts me for "Enter...format"
and I enter any number i.e. 231314

I get no output?

and even a number like 251617 which is not in the format I should get an output "No such time!"

but if I enter characters i.e. ahdbsh, then I get "No such time"
which is what I want but I need it for numbers to.

Any thoughts on what mistakes I have made

Thanks.
 
Last edited by a moderator:

jaduff46

macrumors 6502
Mar 3, 2010
328
187
Second star on the right....
Another approach which I've used in the past is to use gets() to get a character string, then use sscanf (like scanf) on the string to get the data you want.

Benefits are that it will return the number of arguments converted (3 in your case, EOF on an error) and I find it easier to control (don't have to worry about flushing the stdin buffer on an error)

Admittedly haven't had to do this in awhile.
 

Cromulent

macrumors 604
Oct 2, 2006
6,802
1,096
The Land of Hope and Glory
Another approach which I've used in the past is to use gets() to get a character string, then use sscanf (like scanf) on the string to get the data you want.

I'm surprised you didn't get a warning when using gets(). The Mac OS X implementation (and probably most others) prints a line to stdout when using the gets() function that explicitly states that you shouldn't use it.

In fact gets() is so bad it has been completely removed from the new C standard C11.
 
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