Iterating over 3D Arrays

Question

I keep on getting this Bus Error 10 on my code and I have no idea why.

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

#define SIZE 100

int main() {

    char input[SIZE];

    int dummy[SIZE];

    int array[SIZE][SIZE][SIZE];

    int set=-1;
    int sequence=0;


    while (1==1) {
       if (fgets(input, SIZE-1, stdin) == NULL){
         printf("Input Error.");
         break;
       }else {

         char* s;

         for (s = input; (*s != '\n') && isspace(*s); s++){
            ; 
         }

         if (*s == 'f'){ //start of finish

            break; 

         } else if (*s == 'S'){ //start of SET

            set++;

         } else{

            sscanf(input, "%d: %d, %d, %d, %d, %d", &dummy[0], 
            &dummy[1], &dummy[2], &dummy[3], &dummy[4], 
            &dummy[5]);

            array[set][sequence][0]=dummy[0];

            array[set][sequence][1]= 
            dummy[1]+dummy[2]+dummy[3]+dummy[4]+dummy[5];

            sequence++;

         }

       }
     }

    for (int i=0; i<sizeof(array); i++ ){
        printf("SET %d\n", i+1);
        for (int j=0; j<sequence;j++){
            printf("%d", array[i][j][0]);
            for (int k=0; k<=5; k++){
                printf("%d\n", array[i][j][1]);
            }
        }
    }

    return 0;
}

Basically if I have an input of a certain number of sets and a sequence of numbers. Like so:

SET 1

1: 5,5,6,5
2: 3,4,5,5
3: 3,4,5,6

SET 2

1: 5,7,8,7
2: 5,5,5,6


finish

I want to output the sequence number and sum of all the number after the colon for each sequence in a given set. So it would look something like this.

But, when I try to execute my code, I get Bus Error: 10. I tried resizing the array but now I can't iterate over my array since it keep returning a bunch of random number. Like:

-34618613832766
32766
32766
32766
32766
32766
1178023731825050672
825050672
825050672

Where are these numbers from? thanks.

Why not start testing with a number significantly smaller, let's say 100? — alk, Oct 01 '18 at 09:37
I tried setting SIZE to 1000 but I got Segmentation Fault 11 instead, which confused me even more. — William, Oct 01 '18 at 09:37
Go for the smaller and then you might like to read this: [How to debug small programs](https://ericlippert.com/2014/03/05/how-to-debug-small-programs/) — alk, Oct 01 '18 at 09:38
`array` is like 2*910 terabytes big (assuming `sizeof(int) = 2`). You must have a big machine. — KamilCuk, Oct 01 '18 at 09:40
I also tried doing 100 but the program wasn't printing anything when I did. I think it was because it was not enough, — William, Oct 01 '18 at 09:41
You need to rethink the design. array should be allocated dynamically. Also you don't need the 3rd dimension to be `SIZE` big, only 2. — KamilCuk, Oct 01 '18 at 09:42
`input` can be dynamically allocated, you can use [getline](https://linux.die.net/man/3/getline) or for ex. [cs50 library](https://github.com/cs50/libcs50/blob/develop/src/cs50.h#L219) or write your own. Also dummy just needs 6 elements, not 10000. — KamilCuk, Oct 01 '18 at 09:48
You can't allocate thousands of terabyte on the stack, simple as that. Nothing else needs to be said. — Lundin, Oct 01 '18 at 09:53
William, On a minor note, the `-1` in `char input[SIZE]; ... fgets(input, SIZE - 1, stdin)` is not needed. Further, recommend `fgets(input, sizeof input, stdin)` instead. — chux - Reinstate Monica, Oct 01 '18 at 15:24

score 1 · Answer 1 · answered Oct 01 '18 at 09:47

1

Your arrays are most likely too big for the stack. Consult your compilers manual on how to increase the stack size or allocate them dynamically on the free store (aka "heap") using malloc().

answered Oct 01 '18 at 09:47

Swordfish

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Iterating over 3D Arrays

1 Answers1