Thread: Program skipping while loop

I basically got two problems, I get a control reaches end of non void function warning in my function even though I got a return.

And secondly my get char in the while loop near the end of the main function is not being evaluated, the program just ends after I enter a team letter, it wasn't doing this earlier when I used scanf instead of get char, but scanf was giving me character constant too long warning.

Code:

//ASSIGNMENT 1

#include <stdio.h>

#define RETURN '\n'
#define PRINT_SCORE 1

char gameScore (char s);


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

  char team;//Team
  char s;
  char teamA;
  char teamB;


  printf ("Which team to serve? A or B?\n");
  scanf ("%c", &team);

  if ( team  == 'A') {
    printf ("Team A to serve:\n");
  }  
  else if ( team == 'B'){
    printf ("Team B to serve:\n");
    }
  else{
    printf ("Incorrect entry, try again\n");
    return 0;
  }  

  while ((s = getchar()) != '\n') {
   
    if (gameScore( s ) == PRINT_SCORE){
      printf("%d-%d\n", teamA, teamB);
    }
  }     
     

return (0);
}

char gameScore (char s){

  int teamA;
  int teamB;

  teamA = 0;
  teamB = 0;

  if(s == 'A'){
    teamA = teamA+15;
  }
  
  else if(s == 'B'){
    teamB = teamB+15;
  }  
  
  else if(s == 'S'){
    return(PRINT_SCORE);
  }
  
}

Any help would be greatly appreciated, cheers

But i'm not concerned with it returning anything...yet, I'm just wondering why it doesn't even get to the while loop but just heads to return 0;

The FAQ wasn't entirely helpful, unless you mean I have to clear my input buffer before going into the while loop ??? :S?

Thanks for letting me know I have to put return 0 for the other function btw

Well you've got some problems. Let's talk about your function first.

Code:

char gameScore (char s);

If you write a function prototype such that it returns a value, you have to return something for all code paths. It doesn't matter which team's score you need to retrieve, even if you don't know which team the user is talking about, you have to return a value.

You should also return values that agree with the type. While there is nothing wrong per se with returning 1 as a char, it is different than returning something like 'f'. It would make more sense to return an integer because that is what 1 is.

Code:

  if(s == 'A'){
    teamA = teamA+15;
  }
  
  else if(s == 'B'){
    teamB = teamB+15;
  }

I've also noticed that you seem to think that team variables will increase with each call to your function, but this won't be the case. A function's argument is a copy of the variable it is passed, so that any changes you make to the argument will not affect similar variables elsewhere.

What teamA contains in main will always be different than teamA in getScore.

In order to change something purposefully, it can be easiest to pass a pointer containing the address of the object you want to change.

Code:

 while ((s = getchar()) != '\n') {
   
    if (gameScore( s ) == PRINT_SCORE){
      printf("%d-%d\n", teamA, teamB);
    }

scanf will keave characters that aren't part of a format in your input stream. Characters like '\n'. So, functions like getchar() will read them, and usually your loops will break after one turn.

> As for pointers, not learnt them yet, so I can't use it

Well I guess the teamA and teamB variables could be global (so that they could be updated regardless of scope), but pointers are better in this situation. Or use an array to represent scores. If you're interested in working ahead of the class, use the internet to learn about them, and then use them here.

Either way, bother your professor about it soon. It's bread-and-butter type of knowledge.

Originally Posted by citizen

> As for pointers, not learnt them yet, so I can't use it

Well I guess the teamA and teamB variables could be global (so that they could be updated regardless of scope), but pointers are better in this situation. Or use an array to represent scores. If you're interested in working ahead of the class, use the internet to learn about them, and then use them here.

Either way, bother your professor about it soon. It's bread-and-butter type of knowledge.

Aha, global variables! I forgot about them, now I seem to be getting somewhere, thanks a lot dude! Now things should start falling into place.

If they are global variables, then if the variable is used in one function and it's value changes, and you use that variable in another function, say the main, the value should be identical right?