How to get rid of seemingly random 0's generated by the strtol function?

Question

I am dealing with this while loop below:

while (fgets(binaryArray, MAX_COLUMNS, file)) {

int index = 0, index2 = 0;

while (binaryArray[index] != '\0'){

if (binaryArray[index] != ' ') {
binaryArray[index2++] = binaryArray[index];
}

index++;
}

binaryArray[index2]='\0';

//printf("%s", binaryArray);
printf("%ld\n", strtol(binaryArray, NULL, 2));
}

===========================================

When the printf("%s", binaryArray); is uncommented (and the printf("%ld\n", strtol(binaryArray, NULL, 2)); is commented out), I get desired binary numbers (without white space between the bits):

10101
10001
00011
10111

However, when the printf("%s", binaryArray); is commented out and the printf("%ld\n", strtol(binaryArray, NULL, 2)); is uncommented, I get the desired decimal values, but with unwanted 0's in between each print:

0
21
0
17
0
3
0
23
0
0

Could you explain why this is happening, and how I could prevent it from happening?

==========================================
Entire code: https://code.sololearn.com/cPjtXK5U7u0V

input text file has this:
4 5
1 0 1 0 1
1 0 0 0 1
0 0 0 1 1
1 0 1 1 1

Answer 1

First problem arises in printDecimalDigits. Add a '\n' to the scanf:

void printDecimalDigits(char *fileName) {
int fileNumRows;
int fileNumColumns;
char binaryArray[MAX_COLUMNS];
FILE *file = fopen(fileName, "r");
fscanf(
file,
"%d %d\n",
&fileNumRows,
&fileNumColumns
);

Otherwise, the file pointer will point to that character, and that is what is messing up your output.

Next, set MAX_COLUMNS to 11, otherwise fgets will not read the '\n' char again from the file.

#define MAX_COLUMNS 11

Answer 2

@Ani Jona

Better now, thank you. However, there's still a 0 at the end. I'll look into this a bit more.

Answer 3

May be there is an empty row? I only wrote the file here in the playground from the info you provided. If so, then you may need to check for and skip empty lines.