for (x = 0, y = 0 ; y < size_y ; y++)
    for (x = 0; x < size_x ; x++)
      {
        printf("%d : %d", y, x);
        if (tab[y][x] == '.')
          {
            while (calc_carre(tab, x, y, size_carre) == 1)
              size_carre++;
            my_printf("%d\n", size_carre);
          }
      }