Floating Point Exception

[Mentallic]

I have a code in which I enter a 12 or 13 digit number and it does a few calculations here and there, then it spits out the barcode again with a few extra details.
When I enter a 13 digit number it works fine, and before I "fixed" my code, at least it was taking in a 12 digit number and spitting out the wrong values, but now it just says "floating point error".

What is this, and where exactly am I going wrong?

#include <stdio.h>
#include <assert.h>

#define UPPER_LIMIT 10000000000000LL
#define LOWER_LIMIT 100000000000LL

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

    long long barcode = 0;
    int partOne = 0;
    int partTwo = 0;
    int partThree = 0;
    int partFour = 0;
    int numScanned = -1;
    long long i = 0;
    long long j = 0;
    int subTotal = 0;
    int sumEven = 0;
    int sumOdd = 0;
    int checkSum = -1;
    int digitFlag = 0;

    printf("Enter barcode: ");
    numScanned = scanf("%lld", &barcode);
    
    assert( (numScanned == 1) && ((barcode / LOWER_LIMIT) != 0) );
    
    partOne = barcode / 10000000000LL;
    partTwo = ( barcode / 10000 ) % 1000000;
    partThree = ( barcode / 10 ) % 1000;
    partFour = barcode % 10;
    
    //checksum for 12 digit barcode
    if ( (barcode / (10*LOWER_LIMIT)) == 0 ) {
        for ( i = LOWER_LIMIT; i >= 0; i = i/100 ) {
            subTotal = (barcode / i) % 10;
            sumEven = sumEven + subTotal;
            //printf("sumeven %d\n", sumEven);
        }
        for ( j = LOWER_LIMIT / 10; j > 0; j = j/100 ) {
            subTotal = 3 * ( (barcode / j) % 10);
            sumOdd = sumOdd + subTotal;
            //printf("sumodd %d\n", sumOdd);
        }
        checkSum = (sumOdd + sumEven) % 10;
        
        if (checkSum != 0) {
            checkSum = 10 - checkSum;
        }
        
        digitFlag = 12;
        
    } else { //checksum for 13 digit barcode
        for ( i = 10 * LOWER_LIMIT; i > 10; i = i/100 ) {
            subTotal = (barcode / i) % 10;
            sumEven = sumEven + subTotal;
            printf("sumeven %d\n", sumEven);
        }
        for ( j = LOWER_LIMIT; j > 0; j = j/100 ) {
            subTotal = 3 * ( (barcode / j) % 10);
            sumOdd = sumOdd + subTotal;
            printf("sumodd %d\n", sumOdd);
        }
        checkSum = (sumOdd + sumEven) % 10;
        
        if (checkSum != 0) {
            checkSum = 10 - checkSum;
        }
        
        digitFlag = 13;
        
    }
        
    
    printf("\nBarcode is ");
        
    //print the 12 digit barcode with the checksum
    if (digitFlag == 12) {
        printf("%d-%06d-%03d-%d\n", 10*partOne + partTwo/100000, 
        10*(partTwo % 100000) + partThree/100,
        10*(partThree % 100) + partFour, 
        checkSum);
    } else if (digitFlag == 13) { //print 13 digit barcode and check valid
        printf("%d-%06d-%03d-%d\n", partOne, partTwo, partThree, partFour);
        printf("Checksum is %d\n", checkSum);
        if (checkSum == partFour) {
            printf("Barcode is valid\n");
        } else {
            printf("Barcode is invalid\n");
        }
    }
    
    
    return 0;
}

[Prelude]

for ( i = LOWER_LIMIT; i >= 0; i = i/100 ) {
    subTotal = (barcode / i) % 10;

When i reaches 0, you're dividing by 0 in the next statement. I don't suspect that was intended, perhaps you accidentally used >= in the loop condition rather than >?

[Mentallic]

Oh yes of course. No idea why I chose >= that time. Thanks for spotting it!