# Working on a Sudoku Solver in Python (Source Code)

This is a document previous to a live code review session.

It has the information to prepare for the upcoming code review session, where I plan to share the lessons learned, decision I took, mistakes I did, refactors I had to overcome, and tentatively we will refactor code in order to add some Unit Testing.

## History

I used to play sudoku with my family, so from time to time I do by myself.

Once I found a sudoku that was impossible and it happened that it was a typo from the newspaper, so, when I found another impossible sudoku I wanted to know if it was me, or if there was a typo or similar, so I decided to write a Sudoku Solver that will solve the sudoku for me.

I had problems solving these two sudokus:

## The Source Code

You can clone the project from here:

https://gitlab.com/carles.mateo/sudo-ku-solver

You will have to install colorama package, as I used it for giving colors to the output:

`pip3 install colorama`

The main program sudokusolver.py:

```import copy
from lib.colorutils import ColorUtils

class SudokuMap():

def __init__(self, i_width, i_height, o_color=ColorUtils()):
self.i_width = i_width
self.i_height = i_height
self.o_color = o_color

self.a_map = self.generate_empty_map()

def generate_empty_map(self):
a_map = []
a_row = []
a_i_possible_numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9]
for i_x in range(self.i_width):
a_row.append(a_i_possible_numbers.copy())

for i_y in range(self.i_height):
a_map.append(copy.deepcopy(a_row))

return a_map

def set_number(self, i_number, i_x, i_y):
"""
Sets a well known (already defined in the original map) number for a position
:param i_number:
:param i_x:
:param i_y:
:return:
"""
self.a_map[i_y][i_x] = [i_number]

def detect_and_remove_a_number_from_possibles_from_a_row(self, i_y):
"""
We will elinate this possibility from the row
:return: Boolean
"""

b_found = False
self.o_color.print_label("Detecting numbers to remove from row " + str(i_y))

for i_x in range(0, self.i_width):
a_i_numbers_possible = self.a_map[i_y][i_x]
if len(a_i_numbers_possible) == 1:
b_found = True
i_number_found = self.a_map[i_y][i_x][0]
print("Found a number that will be removed from horizontal and vertical and in quadrant", i_number_found, "at", i_x, i_y)
self.remove_a_number_from_possibles_in_a_row(i_number_to_remove=i_number_found, i_y=i_y)
self.remove_a_number_from_possibles_in_a_column(i_number_to_remove=i_number_found, i_x=i_x)

return b_found

def remove_a_number_from_possibles_in_a_row(self, i_number_to_remove, i_y):
"""
Removes a number from the list of possibles in that row
:param i_number_to_remove:
:param i_y:
:return:
"""

self.o_color.print_label("> Scanning for removing " + str(i_number_to_remove) + " in row " + str(i_y))

for i_x in range(0, self.i_width):
a_i_numbers_possible = self.a_map[i_y][i_x]
if len(a_i_numbers_possible) == 1 and a_i_numbers_possible[0] == i_number_to_remove:
# This is the right cell, ignore it
pass
else:
# Subtract the number from the sequence
if i_number_to_remove in a_i_numbers_possible:
a_i_numbers_possible_old = a_i_numbers_possible.copy()
a_i_numbers_possible.remove(i_number_to_remove)
print("> Removed", i_number_to_remove, "From:", str(i_x) + "x" + str(i_y), a_i_numbers_possible_old, "Pending:", a_i_numbers_possible)
self.a_map[i_y][i_x] = a_i_numbers_possible
if len(a_i_numbers_possible) == 1:
# Trigger it again for the number recently discovered
i_new_number_to_remove = a_i_numbers_possible[0]
self.o_color.print_success("> Found " + str(i_new_number_to_remove) + " From: " + str(i_x) + "x" + str(i_y))
self.remove_a_number_from_possibles_in_a_row(i_number_to_remove=i_new_number_to_remove, i_y=i_y)
self.remove_a_number_from_possibles_in_a_column(i_number_to_remove=i_new_number_to_remove, i_x=i_x)

self.o_color.print_label("> Leaving scan for " + str(i_number_to_remove) + " in row " + str(i_y))

def remove_a_number_from_possibles_in_a_column(self, i_number_to_remove, i_x):
"""
Removes a number from the list of possibles in that row
:param i_number_to_remove:
:param i_y:
:return:
"""

self.o_color.print_label("V Scanning for removing " + str(i_number_to_remove) + " in col " + str(i_x))

for i_y in range(0, self.i_height):
a_i_numbers_possible = self.a_map[i_y][i_x]
if len(a_i_numbers_possible) == 1 and a_i_numbers_possible[0] == i_number_to_remove:
# This is the right cell, ignore it
pass
else:
# Subtract the number from the sequence
if i_number_to_remove in a_i_numbers_possible:
a_i_numbers_possible_old = a_i_numbers_possible.copy()
a_i_numbers_possible.remove(i_number_to_remove)
print("V Removed", i_number_to_remove, "From:", i_x, i_y, a_i_numbers_possible_old, "Pending:", a_i_numbers_possible)
# @TODO: Remove, as it's a pointer it is not needed
self.a_map[i_y][i_x] = a_i_numbers_possible
if len(a_i_numbers_possible) == 1:
# Trigger it again for the number recently discovered
i_new_number_to_remove = a_i_numbers_possible[0]
self.o_color.print_success("Found " + str(i_new_number_to_remove) + " From: " + str(i_x) + " " + str(i_y))
self.remove_a_number_from_possibles_in_a_row(i_number_to_remove=i_new_number_to_remove, i_y=i_y)
self.remove_a_number_from_possibles_in_a_column(i_number_to_remove=i_new_number_to_remove, i_x=i_x)

self.o_color.print_label("V Leaving scan for " + str(i_number_to_remove) + " in col " + str(i_x))

"""

:param i_number_to_remove:
:param i_x:
:param i_y:
:return:
"""

i_x_end = i_x_ini + 2

i_y_end = i_y_ini + 2

for i_y_rel in range(i_y_ini, i_y_end + 1):
for i_x_rel in range(i_x_ini, i_x_end + 1):
a_i_numbers_possible = self.a_map[i_y_rel][i_x_rel]
if len(a_i_numbers_possible) == 1 and a_i_numbers_possible[0] == i_number_to_remove:
# This is the right cell, ignore it
pass
else:
# Subtract the number from the sequence
if i_number_to_remove in a_i_numbers_possible:
a_i_numbers_possible_old = a_i_numbers_possible.copy()
a_i_numbers_possible.remove(i_number_to_remove)
print("X Removed", i_number_to_remove, "From:", i_x_rel, i_y_rel, a_i_numbers_possible_old, "Pending:", a_i_numbers_possible)
# Nota: Here I had a bug and I was "liant-la parda"
# if len(a_i_numbers_possible) == 1:
#     # Trigger it again for the number recently discovered
#     i_new_number_to_remove = a_i_numbers_possible[0]
#     string_ints = [str(int) for int in ints]
#     self.o_color.print_success("X Found " + str(i_new_number_to_remove) + " From: " + str(i_x) + "x" + str(i_y) + "[]")
#     self.remove_a_number_from_possibles_in_a_row(i_number_to_remove=i_new_number_to_remove, i_y=i_y)
#     self.remove_a_number_from_possibles_in_a_column(i_number_to_remove=i_new_number_to_remove, i_x=i_x)

"""

:param i_number_to_remove:
:param i_x:
:param i_y:
:return: b_found
"""

i_x_end = i_x_ini + 2

i_y_end = i_y_ini + 2

i_number_of_occurrences_found = 0
i_x_position_number = 0
i_y_position_number = 0

b_unique = False

for i_y_rel in range(i_y_ini, i_y_end + 1):
for i_x_rel in range(i_x_ini, i_x_end + 1):
a_i_numbers_possible = self.a_map[i_y_rel][i_x_rel]
for i_number_in_possibles in a_i_numbers_possible:
if len(a_i_numbers_possible) > 1 and i_number_in_possibles == i_number_to_check:
# This is the right cell, ignore it
i_number_of_occurrences_found += 1
i_x_position_number = i_x_rel
i_y_position_number = i_y_rel
if i_number_of_occurrences_found > 1:
# Unsuccessful
break

if i_number_of_occurrences_found == 1:
# Success!
a_i_numbers_possible = [i_number_to_check]
self.a_map[i_y_position_number][i_x_position_number] = a_i_numbers_possible
b_unique = True

return b_unique, i_x_position_number, i_y_position_number

def check_if_number_possibles_in_row_is_unique(self, i_number_to_check, i_y):
"""

:param i_number_to_check:
:param i_x:
:param i_y:
:return:
"""

i_number_of_occurrences_found = 0
i_x_position_number = 0
i_y_position_number = 0

b_unique = False

for i_x_rel in range(0, 9):
a_i_numbers_possible = self.a_map[i_y][i_x_rel]
for i_number_in_possibles in a_i_numbers_possible:
if len(a_i_numbers_possible) > 1 and i_number_in_possibles == i_number_to_check:
# This is the right cell, ignore it
i_number_of_occurrences_found += 1
i_x_position_number = i_x_rel
i_y_position_number = i_y
if i_number_of_occurrences_found > 1:
# Unsuccessful
break

if i_number_of_occurrences_found == 1:
# Success!
a_i_numbers_possible = [i_number_to_check]
self.a_map[i_y_position_number][i_x_position_number] = a_i_numbers_possible
b_unique = True

return b_unique, i_x_position_number, i_y_position_number

def get_map_drawing_as_string(self, a_map_alternative=None):
s_map = ""
i_counter_y = 0
s_separator_rows = "="

a_map_to_use = self.a_map
if a_map_alternative is not None:
a_map_to_use = a_map_alternative

s_map = s_map + s_separator_rows * 37 + "\n"
for a_row in a_map_to_use:
i_counter_y += 1
if i_counter_y == 3:
i_counter_y = 0
s_separator_rows = "="
else:
s_separator_rows = "-"

s_map = s_map + "|"
i_counter = 0
for a_i_numbers_possible in a_row:
i_counter += 1

if len(a_i_numbers_possible) == 1:
s_number = str(a_i_numbers_possible[0])
else:
s_number = " "

if i_counter == 3:
s_separator = "|"
i_counter = 0
else:
s_separator = "¦"
s_map = s_map + " " + s_number + " " + s_separator
s_map = s_map + "\n"

s_map = s_map + s_separator_rows * 37 + "\n"

# Replace 0 by " "
s_map = s_map.replace("0", " ")

s_map = s_map + "\n\n"
i_total_numbers_found, a_s_numbers_found = self.get_total_numbers_found()
s_map = s_map + "Total numbers found: " + str(i_total_numbers_found) + " Numbers found: " + " ".join(a_s_numbers_found) + "\n"

return s_map

def get_map_drawing_of_possibles_as_string(self, a_map_alternative=None):
s_map = ""
i_counter_y = 0
s_separator_rows = "="

a_map_to_use = self.a_map
if a_map_alternative is not None:
a_map_to_use = a_map_alternative

s_map = s_map + self.o_color.color_blue(s_separator_rows * ((9 * ( 9 + 2 )) + 10)) + "\n"
for a_row in a_map_to_use:
i_counter_y += 1
if i_counter_y == 3:
i_counter_y = 0
s_separator_rows = "="
else:
s_separator_rows = "-"

s_map = s_map + self.o_color.color_blue("|")
i_counter = 0
for a_i_numbers_possible in a_row:
i_counter += 1

if len(a_i_numbers_possible) == 1:
# The right number
s_number = str(a_i_numbers_possible[0]).center(9)
s_number = self.o_color.color_success(s_number)
else:
a_i_numbers_possible_string = []
for i_number in a_i_numbers_possible:
s_number = str(i_number)
# Replace by the color sequence
if i_number == 2:
s_number = self.o_color.color_red(s_number)
if i_number == 3:
s_number = self.o_color.color_yellow(s_number)
if i_number == 4:
self.o_color.color_magenta(s_number)
a_i_numbers_possible_string.append(s_number)
# s_number = "".join(a_i_numbers_possible_string).ljust(9)
s_number = "".join(a_i_numbers_possible_string) + " " * (9-len(a_i_numbers_possible))

if i_counter == 3:
s_separator = self.o_color.color_blue("|")
i_counter = 0
else:
s_separator = self.o_color.color_blue("¦")
s_map = s_map + " " + s_number + " " + s_separator
s_map = s_map + "\n"

s_map = s_map + self.o_color.color_blue(s_separator_rows * ((9 * (9 + 2)) + 10)) + "\n"

# Replace 0 by " "
s_map = s_map.replace("0", " ")

return s_map

def get_total_numbers_found(self):

i_total_numbers_found = 0
a_s_numbers_found = []

for i_y in range(0, self.i_height):
for i_x in range(0, self.i_width):
a_i_numbers_possible = self.a_map[i_y][i_x]
if len(a_i_numbers_possible) == 1:
i_total_numbers_found = i_total_numbers_found + 1
i_number_found = self.a_map[i_y][i_x][0]
s_number_found = str(i_number_found)
if s_number_found not in a_s_numbers_found:
a_s_numbers_found.append(s_number_found)

return i_total_numbers_found, a_s_numbers_found

if __name__ == "__main__":

o_color = ColorUtils()

o_map = SudokuMap(9, 9, o_color=o_color)
o_map.set_number(i_number=1, i_x=1, i_y=0)
o_map.set_number(3, 4, 0)
o_map.set_number(8, 7, 0)

o_map.set_number(8, 0, 1)
o_map.set_number(7, 3, 1)
o_map.set_number(4, 5, 1)
o_map.set_number(6, 8, 1)

o_map.set_number(3, 2, 2)
o_map.set_number(9, 6, 2)

o_map.set_number(2, 1, 3)
o_map.set_number(4, 4, 3)
o_map.set_number(6, 7, 3)

o_map.set_number(5, 0, 4)
o_map.set_number(6, 3, 4)
o_map.set_number(2, 5, 4)
o_map.set_number(8, 8, 4)

o_map.set_number(3, 1, 5)
o_map.set_number(8, 4, 5)
o_map.set_number(7, 7, 5)

o_map.set_number(2, 2, 6)
o_map.set_number(6, 6, 6)

o_map.set_number(9, 0, 7)
o_map.set_number(4, 3, 7)
o_map.set_number(3, 5, 7)
o_map.set_number(2, 8, 7)

o_map.set_number(8, 1, 8)
o_map.set_number(6, 4, 8)
o_map.set_number(1, 7, 8)

# Extra
# o_map.set_number(2, 0, 0)

# Speculative
o_map.set_number(7, 0, 3)

# Another map
o_map2 = SudokuMap(9, 9, o_color=o_color)
o_map2.set_number(i_number=5, i_x=0, i_y=0)
o_map2.set_number(i_number=9, i_x=5, i_y=0)

o_map2.set_number(i_number=7, i_x=2, i_y=1)
o_map2.set_number(i_number=2, i_x=7, i_y=1)

o_map2.set_number(i_number=2, i_x=0, i_y=2)
o_map2.set_number(i_number=3, i_x=4, i_y=2)
o_map2.set_number(i_number=1, i_x=5, i_y=2)
o_map2.set_number(i_number=9, i_x=7, i_y=2)

o_map2.set_number(i_number=7, i_x=0, i_y=3)
o_map2.set_number(i_number=1, i_x=2, i_y=3)
o_map2.set_number(i_number=6, i_x=3, i_y=3)
o_map2.set_number(i_number=9, i_x=4, i_y=3)
o_map2.set_number(i_number=4, i_x=8, i_y=3)

o_map2.set_number(i_number=1, i_x=4, i_y=4)

o_map2.set_number(i_number=6, i_x=0, i_y=5)
o_map2.set_number(i_number=7, i_x=4, i_y=5)
o_map2.set_number(i_number=4, i_x=5, i_y=5)
o_map2.set_number(i_number=3, i_x=6, i_y=5)
o_map2.set_number(i_number=1, i_x=8, i_y=5)

o_map2.set_number(i_number=5, i_x=1, i_y=6)
o_map2.set_number(i_number=3, i_x=3, i_y=6)
o_map2.set_number(i_number=6, i_x=4, i_y=6)
o_map2.set_number(i_number=8, i_x=8, i_y=6)

o_map2.set_number(i_number=6, i_x=1, i_y=7)
o_map2.set_number(i_number=7, i_x=6, i_y=7)

o_map2.set_number(i_number=9, i_x=3, i_y=8)
o_map2.set_number(i_number=3, i_x=8, i_y=8)

# Extra help while not implemented the best algorithm
# =============================================================================================================
# |     5     ¦ 148       ¦ 48        |     7     ¦     2     ¦     9     | 148       ¦     3     ¦     6     |
# -------------------------------------------------------------------------------------------------------------
# | 13489     ¦ 13489     ¦     7     | 48        ¦ 48        ¦     6     | 148       ¦     2     ¦     5     |
# -------------------------------------------------------------------------------------------------------------
# |     2     ¦ 48        ¦     6     |     5     ¦     3     ¦     1     | 48        ¦     9     ¦     7     |
# =============================================================================================================
# |     7     ¦ 38        ¦     1     |     6     ¦     9     ¦ 358       |     2     ¦ 58        ¦     4     |
# -------------------------------------------------------------------------------------------------------------
# | 348       ¦ 2348      ¦ 3458      | 28        ¦     1     ¦ 358       |     6     ¦     7     ¦     9     |
# -------------------------------------------------------------------------------------------------------------
# |     6     ¦ 289       ¦ 589       | 28        ¦     7     ¦     4     |     3     ¦ 58        ¦     1     |
# =============================================================================================================
# | 14        ¦     5     ¦     2     |     3     ¦     6     ¦     7     |     9     ¦ 14        ¦     8     |
# -------------------------------------------------------------------------------------------------------------
# | 3489      ¦     6     ¦ 3489      |     1     ¦ 458       ¦ 58        |     7     ¦ 45        ¦     2     |
# -------------------------------------------------------------------------------------------------------------
# | 148       ¦     7     ¦ 48        |     9     ¦ 458       ¦     2     | 145       ¦     6     ¦     3     |
# =============================================================================================================
# By best algorithm I mean that the last in the middle vertical quadrant from the top right horizontally,
# only 5 can be in a column. That clarifies that 5 must go to the other column in last quadrant, first column. Coord 6x8
# o_map2.set_number(i_number=5, i_x=6, i_y=8)
# ERROR traces from a bug fixed to mentioned during the code review
# Surprisingly this fails
# > Leaving scan for 8 in row1
# V Scanning for removing 8 in col 4
# V Removed 8 From: 4 7 [5, 8] Pending: [5]
# Found 5 From: 4 7
#
# > Scanning for removing 5 in row 7
# > Removed 5 From: 5 7 [5, 8] Pending: [8]
# > Found 8 From: 5 7
#
# > Scanning for removing 8 in row 7
# > Removed 8 From: 0 7 [3, 8] Pending: [3]
# > Found 3 From: 0 7

o_map = o_map2

print(o_map.get_map_drawing_as_string())

b_changes_found = True
while b_changes_found is True:
b_changes_found = False

for i_y in range(0, o_map.i_height):
b_found = o_map.detect_and_remove_a_number_from_possibles_from_a_row(i_y=i_y)
if b_found is True:
print(o_map.get_map_drawing_as_string())

for i_y in range(0, o_map.i_height):
o_map.o_color.print_label("Scanning quadrants for row " + str(i_y))
for i_number in range(1, 10):
for i_x in range(0, o_map.i_width):
b_found, i_x_found, i_y_found = o_map.check_if_number_possibles_in_quadrant_is_unique(i_number_to_check=i_number, i_x=i_x, i_y=i_y)
if b_found is True:
# Search again
b_changes_found = True
o_map.remove_a_number_from_possibles_in_a_row(i_number_to_remove=i_number, i_y=i_y_found)
o_map.remove_a_number_from_possibles_in_a_column(i_number_to_remove=i_number, i_x=i_x_found)

b_found, i_x_found, i_y_found = o_map.check_if_number_possibles_in_row_is_unique(i_number_to_check=i_number, i_y=i_y)
if b_found is True:
b_changes_found = True
o_map.remove_a_number_from_possibles_in_a_column(i_number_to_remove=i_number, i_x=i_x_found)

if b_changes_found is True:
print(o_map.get_map_drawing_as_string())

# @TODO: Implement check if number in quadrant can only go to a column, to remove the non possible in that column from another quadrant
# @TODO: Implement check if in a line only one number can go to a column.

print(o_map.get_map_drawing_as_string())
print(o_map.get_map_drawing_of_possibles_as_string())
```

The color library lib/colorutils.py:

```from colorama import Fore, Back, Style , init

class ColorUtils:

def __init__(self):
# For Colorama on Windows
init()

def print_error(self, m_text, s_end="\n"):
"""
Prints errors in Red.
:param s_text:
:return:
"""

# If they pass numbers
s_text = str(m_text)

print(Fore.RED + s_text)
print(Style.RESET_ALL, end=s_end)

def print_success(self, m_text, s_end="\n"):
"""
Prints errors in Green.
:param s_text:
:return:
"""

# If they pass numbers
s_text = str(m_text)
print(Fore.GREEN + s_text)
print(Style.RESET_ALL, end=s_end)

def color_success(self, m_text):
"""
Colors only this
:param m_text:
:return:
"""

s_text = str(m_text)
return Fore.GREEN + s_text + Fore.RESET

def color_black(self, m_text):
s_text = str(m_text)
return Fore.BLACK + s_text + Fore.RESET

def color_blue(self, m_text):
s_text = str(m_text)
return Fore.BLUE + s_text + Fore.RESET

def color_red(self, m_text):
s_text = str(m_text)
return Fore.RED + s_text + Fore.RESET

def color_yellow(self, m_text):
s_text = str(m_text)
return Fore.YELLOW + s_text + Fore.RESET

def color_magenta(self, m_text):
s_text = str(m_text)
return Fore.MAGENTA + s_text + Fore.RESET

def print_label(self, m_text, s_end="\n"):
"""
Prints a label and not the end line
:param s_text:
:return:
"""

# If they pass numbers
s_text = str(m_text)

print(Fore.BLUE + s_text, end="")
print(Style.RESET_ALL, end=s_end)

def return_text_blue(self, s_text):
"""
Restuns a Text
:param s_text:
:return: String
"""
s_text_return = Fore.BLUE + s_text + Style.RESET_ALL
return s_text_return
```

# News from the blog 2022-04-22

## Media/Press

I was interviewed by Radio America Barcelona, in their studios in Barcelona.

RAB is a radio for the Catalan diaspora and expats.

The interview was broadcasted by Twitch and can be watched. It’s in Catalan language:

https://www.twitch.tv/videos/1448895585

## Sant Jordi discounted books (promo)

Tomorrow 23th of April is Sant Jordi (Saint George), the patron of Catalonia, and the Catalan traditional celebration consist in this day women gifting a book to the men they love and men gifting a rose to the women they love.

I created a voucher for all my Python books, so, since during 23th of April you can acquire the four books per \$10 USD in total.

This voucher is limited to 100 sales.

https://leanpub.com/b/python3all/c/SANTJORDI2022

## Python 3

I show basically how ASCii characters over 127 are encoded, reducing the maximum length of 255 bytes for the filename.

## ZFS

I’ve updated an article explaining how to create a ZPool raidz (RAID 5 equivalent) from three loop devices based on local files.

Thanks to those that bought my ZFS book this month. :)

## Free books

https://books.goalkicker.com/

## Books I bought

This month I bought these books.

## Firewall

I continued to block any Russian or Belarus Ip Address that connects to the blog.

I also started to block entire ranges of Ip’s from Digital Ocean, as many attacks come from Servers in their infrastructure.

Despite blocking tens of thousands of Ip Addresses, the number of visitors keep growing.

## My Health

Thanks to my strict discipline I managed to recover super well and I’m healthier than before and guided by the satisfied doctors we removed two daily medicines.

I started a new medicine that is for the final phase of my recuperation, which doctors expect to be completely. In fact I’m much more healthier than I was before going to the hospital.

# A super simple HTML jQuery JavaScript to hide a text

Some of my students are working on the Front End part, so I help them with JavaScript and jQuery.

Even if I’m super strong in Back End I’m not bad at JavaScript Front End.

So this super simple code will hide the paragraphs <p> using the hide animation from jQuery.

```<html>
<body>
<p>Text to hide</p>
<input type="button" id="button" value="Hide the text" onclick='\$("p").hide(1000);'>
</body>
</html>```

I think learning should be taken by steps, and starting by the most simple.

# Testing length of Linux ext3/ext4 and ZFS file names with Python 3

Last Update: 2022-04-16 15:22

So, I was working on a project and i wanted to test how long a file can be.

The resources I checked, and also the Kernel and C source I reviewed, were pointing that effectively the limit is 255 characters.

But I had one doubt… given that Python 3 String are UTF-8, and that Linux encode by default is UTF-8, will I be able to use 255 characters length, or this will be reduced as the Strings will be encoded as UTF-8 or Unicode?.

So I did a small Proof of Concept.

For the filenames I grabbed a fragment of the translation to English of the book epic book “Tirant lo Blanc” (The White Knight), one of the first books written in Catalan language and the first chivalry novel known in the world. You can download it for free it in:

https://onlinebooks.library.upenn.edu/webbin/gutbook/lookup?num=378

Python Code:

```from carleslibs.fileutils import FileUtils
from colorama import Fore, Back, Style , init

class ColorUtils:

def __init__(self):
# For Colorama on Windows
init()

def print_error(self, s_text, s_end="\n"):
"""
Prints errors in Red.
:param s_text:
:return:
"""
print(Fore.RED + s_text)
print(Style.RESET_ALL, end=s_end)

def print_success(self, s_text, s_end="\n"):
"""
Prints errors in Green.
:param s_text:
:return:
"""
print(Fore.GREEN + s_text)
print(Style.RESET_ALL, end=s_end)

def print_label(self, s_text, s_end="\n"):
"""
Prints a label and not the end line
:param s_text:
:return:
"""
print(Fore.BLUE + s_text, end="")
print(Style.RESET_ALL, end=s_end)

def return_text_blue(self, s_text):
"""
Restuns a Text
:param s_text:
:return: String
"""
s_text_return = Fore.BLUE + s_text + Style.RESET_ALL
return s_text_return

if __name__ == "__main__":

o_color = ColorUtils()
o_file = FileUtils()

s_text = "In the fertile, rich and lovely island of England there lived a most valiant knight, noble by his lineage and much more for his "
s_text += "courage.  In his great wisdom and ingenuity he had served the profession of chivalry for many years and with a great deal of honor, "
s_text += "and his fame was widely known throughout the world.  His name was Count William of Warwick.  This was a very strong knight "
s_text += "who, in his virile youth, had practiced the use of arms, following wars on sea as well as land, and he had brought many "
s_text += "battles to a successful conclusion."

o_color.print_label("Erasure Code project by Carles Mateo")
print()
print("Task 237 - Proof of Concep of Long File Names, encoded is ASCii, in Linux ext3 and ext4 Filesystems")
print()
print("Using as a sample a text based on the translation of Tirant Lo Blanc")
print("Sample text used:")
print("-"*30)
print(s_text)
print("-" * 30)
print()
print("This test uses the OpenSource libraries from Carles Mateo carleslibs")
print()
print("Initiating tests")
print("================")

if o_file.folder_exists(s_dir) is True:
o_color.print_success("Directory " + s_dir + " already existed, skipping creation")
else:
b_success = o_file.create_folder(s_dir)
if b_success is True:
o_color.print_success("Directory " + s_dir + " created successfully")
else:
o_color.print_error("Directory " + s_dir + " creation failed")
exit(1)

for i_length in range(200, 512, 1):
s_filename = s_dir + "/" + s_text[0:i_length]
b_success = o_file.write(s_file=s_filename, s_text=s_text)
s_output = "Writing file length: "
print(s_output, end="")
o_color.print_label(str(i_length).rjust(3), s_end="")
print(" file name: ", end="")
o_color.print_label(s_filename, s_end="")
print(": ", end="")
if b_success is False:
o_color.print_error("failed", s_end="\n")
exit(0)
else:
o_color.print_success("success", s_end="\n")

# Note: up to 255 work, 256 fails
```

I tried this in an Ubuntu Virtual Box VM.

As part of my tests I tried to add a non typical character in English, ASCii >127, like Ç.

When I use ASCii character < 128 (0 to 127) for the filenames in ext3/ext4 and in a ZFS Pool, I can use 255 positions. But when I add characters that are not typical, like the Catalan ç Ç or accents Àí the space available is reduced, suggesting the characters are being encoded:

Ç has value 128 in the ASCii table and ç 135.

I used my Open Source carleslibs and the package colorama.

Install them with:

`pip3 install carleslibs colorama`

# Some tips for beginners at Elden Ring

Last Update: 2022-05-16 08:03 Irish Time

I played it on Xbox, so these tips are for Xbox.

## Runes

When you kill enemies you get runes.

These are used for increasing your stats or weapons stats.

When you die you’ll lose the runes.

You can recover them if you go to the place where you died. You’ll see them shining on the floor. The place you died is marked on the map.

You’ll not lose things like the map, flowers you picked, etc…

## Horseback mount

After you get the Spectral Steed Whistle bind it to your belt through the inventory or pouch. It looks like a golden ring.

Then you’ll be able to summit it by selecting it (keypad down changes the item selected from the belt) and pressing X.

If you jump over some special spinning wind zones you’ll fly to very high distances.

## You can run/sprint!

That’s something I didn’t see in the controls and I was being killed many many times, so I figured it out there has to be a way to sprint.

You can run by pressing the dodge button, B in XBox. Press B and hold it and move to any direction.

You can also use it when you are mounting Torrent, your horse.

## Rolling dodges some attacks

Some attacks are avoided by rolling.

Mentioned by my friend Cian O’Brien.

## Weight

You can have many items with you, but when you equip them the weight is important.

If you equip too much you’ll be unable jump or roll.

You can have several weapons with you and just equip what you need at each moment (before engaging combat).

## Golden runes

You’ll find golden runes that will be kept in your inventory. They are consumables and you can use them to get instant amount of fragments.

## Summon Ashes spirits

You’ll find spirits that you can summon in points of interest and to fight bosses.

You can balance the number of flasks you have, and increase the number of them by using golden seeds at the sites of grace and the amount of life they replenish if you have the sacred tears.

## Sort Chest

At the sites of grace you can sort your chest, and move things from your inventory to the chest and vice versa.

That’s ideal for reducing the items you carry until the appropriate moment to sell the goods.

## Chests protected by soldiers in cars

You will find some cars protected by soldiers or big monsters.

It took me many time to realize that in the back of them they have a chest.

Jump and open the chest. Good weapons will become handy at an early stage.

## Use the shield

Pressing LB if you have the shield on the left hand will raise the shield and keep it lifted.

This will protect you from incoming attacks.

I killed many enemies and bosses without using the shield, and it was a bit of a pain.

Sekiro style, dying and dying. Raising the shield I was able to beat impossible-to-beat-before bosses easily.

There are head skulls in the map, with bright eyes.

If you crack them hitting with your weapon, you’ll get a golden rune.

You can sell the golden runes to merchants or use them at any time and you’ll get runes. You may have a treasure enough to level up and you may not known.

You don’t loss the golden runes when you die.

## Cycling items in your bag

You can bind several items to your back and cycle them pressing the down key on the pad.

If you bind the healing potion to the first slot in your bag if you hold down the cycle key it will always go back to the first item (thanks Cian!)

My friend Michela says: Carles I suggest if i may put the ring in backup pouch because if you map on the menu where healing potions are you risk to call  the horse when u wanna heal

If you press and hold Y you’ll see the actions that you have mapped in the pouch. So, it’s also a quick way to access these.

## Eliminating groups

Will restore a flask, so you will be able to use another crimson tears. This is capped to your max number of flasks.

## Torch

You can buy a torch and use it. Useful for caves and dark places. Equip it as a weapon and just select it.

## Traveling to the Round Table

When the requirements are met and you travel to the round table, you can go back by opening the map and zooming out. You’ll see then the round table.

## Craft bombs

You can craft bombs if you have recipients to hold them.

Bombs are very useful against some bosses.

In order to craft you’ll need to buy a crafting kit.

## Medallions

Michela also recommends: Bosses use to drop medallions. You can equip them in the medallion/s slot.

## Use Magic

Once you have a spell you can go to a site of grace and select Memorize Spell.

Then with the up path you can switch.

You need to have a casting tool in any hand and press the attack button for that hand in order to perform the sorcery.

I found my first staff in the Sellia Crystal cave, after killing several of these digging blue crystal enemeies, which is a zone where you travel after you open a chest in a cave in Dragon-Buirnt ruins which you access going down stairs in the runes that have the zombies, where the big dragon is. It’s the Digger’s staff.

The centipedes in that area are very hard but I found them very vulnerable to fire bombs that you can craft and to throwing curved knives that you can buy in merchants.

After you defeat a boss in a cave next to a gigantic plant, you can become Sorceress Sellen’s protegee and she will teach you magic (she sell scrolls).

You can give her the academy scroll, IDK if this is good or bad.

## Show glinstone projectiles without aiming

You don’t need to have the focus over an enemy. If you’re looking at the right direction you can just shoot using your staff, and the projectile will go to the enemy automatically.

## Use Incantations

You can use incantations, that are another type of spell.

For doing incantations you need a Sacred Seal.

You can buy one in the two commerce women in the round table.

I discovered this after 82 hours of gameplay.

The incantations are based of faith.

## Kick stairs

Like in Sekiro Shadows die Twice, after you get to certain parts you will be able to kick a stair so you’ll not need to do all the round to get to a boss.

## Try different weapons

Different weapons have different behavior that you may find very convenient.

I recommend you to try different of them.

Some shields parry, which means that if you press the LT action button in the precise moment an enemy attacks, they will become vulnerable for a moment. You can then perform a critical with RB.

## Great Runes

When you defeat one of the mega bosses, the demi gods, you will get a great rune.

You can use the great runes after restoring their power (only once) in a tower.

Then you equip a great rune in a site of grace.

They grant some buffs, but to get the most of them you have to use a Rune Arc.

These are dropped by rats and big rats.

Using a Rune Arc when having a Great Rune active gives you buff, like increased stats, until you die. Then you need another Arc.

I used an Arc for the first time when I was level 77.

## Hashes of war can be duplicated

The hashes of war give special effects to the weapons. To be honest I have been afraid of using it and ruining a good weapon effect, or losing the ash.

But Ashes of war can be duplicated if you have the proper ingredient, in the smith in the Round Table.

I found the first nomadic merchant selling one of these ingredients just after South Raya Lucaria Gate, coming back after traversing the seal, from Main Academy Gate, just walking through the seal, without examining it, and after killing some packs of wolves.

I found this at level 77…

After 120 hours played I was level 83.

After 150 hours played I was level 111 and I had not yet used a single Ash of war.

## Some attacks can be charged

Some attacks, like Loretta’s great arrow, can be charged by holding the fire button.

When it’s fired at its max charge level, it will deal more damage for the same FP cost.

## Don’t roll over poison

In some caves you’ll find poison or rott on the floor. Don’t roll over trying to advance faster. That will cover your clothes with the poison and the disease will continue after you leave the infected zone. Just run or walk.

## Plants in the caves allow you to level up the spirit ashes

The plants that are in the caves, allow to level up the spirit ashes.