Thread: Access Violation

Aright, here it is. This time including the Print function, since it's what's causing me this trouble.

Code:

#include <stdlib.h>
#include <stdio.h>

#define big 2000

struct integer {
	int* digits;
	int size;
};

int i, j, k, stringnum;

int readnum(int stringnum, char* numbr, struct integer *emp);

int main(){
      FILE *ifp;
      char numbr[big];
      struct integer *num = malloc(sizeof(*num));

//Read in the file      
      ifp = fopen("bigint.txt", "r");

//Scan for the number of strings
      fscanf(ifp, "%d", &stringnum);
      
//Read in the numbers
      for (k=0; k<stringnum; k++){
           fscanf(ifp, "%s", numbr);  
           readnum(k, numbr, num);
      }
                       
//Read the array
      printf("\n The arrays are: ");
      for (k=0; k<stringnum; k++){
           for (i=0; i<j; i++)
               printf ("%d ", num[k].digits[i]);
      printf("\n");
      }

      system("PAUSE");
      return 0;
};
int readnum(int stringnum, char* numbr, struct integer *emp){

      int arraysize = strlen(numbr);
      
      emp->digits = malloc(sizeof(*emp->digits) * arraysize);
      
//Move the integer into the array      
      for(i=arraysize, j=0; i>-1; i--){
           if(isdigit(numbr[i])){
               emp->digits[j++] = numbr[i] - '0';
           }
      }
};

You've only got one string. So you had better only print one string.

Before you start the for loop, you had better figure out what j is.

I'm actually not quite sure anymore... originally, it was supposed to be used to flip the array around, but then I just decided to save it in reverse order to begin with, so I guess it became pointless.

How would I set it up so there'd be multiple strings?

EDIT: No, wait, nevermind, j still aids in flipping the array.

In your print loop, j is 12093476102934875-34097850921834701928475-0238947-023498u5-23495u. That is to say, it's random garbage because you never assign it a value.

j is only used in the loops, at the beginning of which it is set to 0.

Also, I'm not sure if this means anything, but there's actually a .txt file that goes with the program. Do you guys need it to help with anything?

Also note that the TXT file I use probably won't have the same number strings as the one in the actual final product, since mine's just a test file.

The contents of the file, if anyone cares:

2
7432968527294356297648975290
2986783975917945029875942976

The first line tells how many strings are in the file, then the subsequent lines are individual strings.

Okay I missed that j is global and so changing it in the function means changing it in main too. Sorry.

However, that does mean that the last one you read is the only one that counts -- if the last one is shorter than the first one, the first one will not print completely. Notice also that each integer object knows how big it is, or is supposed to -- it has a .size element that you have been forgetting to set.

Notice also that you do not have two integer objects, so you cannot read more than one thing at a time. Use a test file with one integer in it, please, and then once you have more than one object you can use a larger file.

Originally Posted by happyclown

Here are some posts of mine with plenty of working sample code for you to learn from:

http://cboard.cprogramming.com/showthread.php?t=111245

http://cboard.cprogramming.com/showthread.php?t=111502

Thanks! I'll take a look at it immediately!

Woah, that's a lot of coding to go though... @_____@

Part of the problem with that is I want to save the string into the array as an integer array, not as a string. Furthermore, part of the assignment was that the structure had to be limited to:

Code:

struct integer {
	int* digits;
	int size;
};

If it wasn't for that second part, I'd try to figure out how to use that code for an integer array over a string, but the limitations on the structure kinda break it. Unless I can somehow do the same thing with this array...

Originally Posted by Graham Aker

Part of the problem with that is I want to save the string into the array as an integer array, not as a string. Furthermore, part of the assignment was that the structure had to be limited to:

Code:

struct integer {
	int* digits;
	int size;
};

If it wasn't for that second part, I'd try to figure out how to use that code for an integer array over a string, but the limitations on the structure kinda break it. Unless I can somehow do the same thing with this array...

You've been trying to fit malloc in all over the place, and you don't know how to get memory for an array? Is this some kind of a troll?