Saving numbers from file to array in C - c

Question

In my code I opened file (succesful) and I am trying to get the numbers to array, but it does not working (control output is bad). Compiler did not show me any error.
link on txt file: https://textuploader.com/1amip
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int main(void) {
FILE *fr_koty;
int **array = NULL;
int x = 1; /* Pocet radku */
int y = 1; /* Pocet sloupcu */
char line[1024];
char *assistant_line;
int number; /* Promena pro cislo*/
char *tab;
if((fr_koty = fopen("koty.txt", "r")) == NULL) {
printf("Soubor se nepodarilo otevrit!");
return 0;
}
while(fgets(line, 1023, fr_koty) != NULL) {
array = (int **) realloc(array, x * sizeof(int *));
array[x] = NULL;
assistant_line = line;
while(sscanf(assistant_line, "%d", &number) == 1) {
array[x] = (int *) realloc(array[x], y * sizeof(int));
array[x][y] = number;
printf("%d ", array[x][y]);
if((tab = strchr(assistant_line, '\t')) != NULL) {
assistant_line = tab + 1;
y++;
}
else {
break;
}
}
putchar('\n');
x++;
}
}
Output of numbers is random. I think the reason is bad working with memory, but I can not see the problem.

Answer 1

You're initializing x and y to 1, which is ok for the realloc, but as C arrays are 0 based, you need to use x-1 and y-1 to access the array elements.
Or you init them to 0 and use (x+1) and (y+1) in the realloc call. I would prefer this way.

Answer 2

Now I see it too. Thank you!
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int main(void) {
FILE *fr_koty;
int **array = NULL;
int x = 1; /* Pocet radku */
int y; /* Pocet sloupcu */
char line[1024];
char *assistant_line;
int number; /* Promena pro cislo*/
char *tab;
if((fr_koty = fopen("koty.txt", "r")) == NULL) {
printf("Soubor se nepodarilo otevrit!");
return 0;
}
while(fgets(line, 1023, fr_koty) != NULL) {
y = 1;
array = (int **) realloc(array, x * sizeof(int *));
array[x-1] = NULL;
assistant_line = line;
while(sscanf(assistant_line, "%d", &number) == 1) {
array[x-1] = (int *) realloc(array[x-1], y * sizeof(int));
array[x-1][y-1] = number;
printf("%d ", array[x-1][y-1]);
if((tab = strchr(assistant_line, '\t')) != NULL) {
assistant_line = tab + 1;
y++;
}
else {
break;
}
}
putchar('\n');
x++;
}
}