HELP! Arithmetic Formatter's output has random F letters on it

[aroddoet]

Tell us what’s happening:
The output on replit’s console has F letters before every Error print, one before one of the operations, and another one just before the output end. I have no idea why, since my code has no F on it. Because of that I am still getting all the failures.
I also get a “None” on the output, but I don’t know if that’s normal or not.
If someone could shine a light on this, I would be very grateful, thank you.

Your code so far

import re

def arithmetic_arranger(problems, sums=False):
  #defining variables
  n1 = ""
  n2 = ""
  op = ""
  sum = ""
  top_list = []
  middle_list = []
  slashes = []
  sums = []
  string = ""

  #first obligatory error checking
  if len(problems) > 5 :
    print('Error: Too many problems.')

  else :

    #splitting the problem for easier manipulation
    for problem in problems:
      n1 = problem.split()[0]
      n2 = problem.split()[2]
      op = problem.split()[1]           
    
      #obligatory error checking
      if op == '/' or op == '*':
        print ("Error: Operator must be '+' or '-'.")

      elif re.search('\D', n1) or re.search('\D', n2) :
        print('Error: Numbers must only contain digits.')

      elif len(n1) >= 5 or len(n2) >= 5 :
        print('Error: Numbers cannot be more than four digits.')        
      
      else :
        #doing the operation for sum=True statements
        if op == "+" :
          sum = str(int(n1) + int(n2))

        elif op == "-" :
          sum = str(int(n1) - int(n2))

        #figuring out the numbers of slashes and spaces needed.
        spaces_n1 = ""
        spaces_n2 = ""       

        if len(n1) >= len(n2) :
          slash = '-' * (len(n1) + 2)
          spaces_n1 = ' ' * (len(slash) - len(n1))
          spaces_n2 = ' ' * ((len(slash) - len(n2)) - 2)
          slashes.extend(slash + "    ")

        elif len(n2) > len(n1) :
          slash = '-' * (len(n2) + 2)
          spaces_n1 = ' ' * (len(slash) - len(n1))
          spaces_n2 = ' ' * ((len(slash) - len(n2)) - 2)
          slashes.extend(slash + "    ")        

        spaces_sum = ' ' * (len(slash) - len(sum))
        
        #appending the parts needed to the lists for printing 
        top_list.extend([spaces_n1, n1, "    "])
        middle_list.extend([op, " ", spaces_n2, n2, "    "])
        sums.extend([spaces_sum, sum + "    "])          
    
        #turning the lists into strings to concatenate in the print statement.
        top_string = ''.join(top_list)
        top_string = top_string.rstrip()
        middle_string = ''.join(middle_list)
        middle_string = middle_string.rstrip()
        slashes_string = ''.join(slashes)
        slashes_string = slashes_string.rstrip()
        sums_string = ''.join(sums)
        sums_string = sums_string.rstrip()

        #check if sums=True for the appropriate print statement
        if sums :
          string = (top_string + "\n" + middle_string + "\n" + slashes_string + "\n" + sums_string + "\n")
          print(string)
        else :
          string = (top_string + "\n" + middle_string + "\n" + slashes_string + "\n")
          print(string)

Output

   32
+ 698
-----
  730

   32      3801
+ 698    -    2
-----    ------
  730      3799

   32      3801      45
+ 698    -    2    + 43
-----    ------    ----
  730      3799      88

   32      3801      45      123
+ 698    -    2    + 43    +  49
-----    ------    ----    -----
  730      3799      88      172

None
    3
+ 855
-----
  858

    3      3801
+ 855    -    2
-----    ------
  858      3799

    3      3801      45
+ 855    -    2    + 43
-----    ------    ----
  858      3799      88

    3      3801      45      123
+ 855    -    2    + 43    +  49
-----    ------    ----    -----
  858      3799      88      172

FError: Operator must be '+' or '-'.
  3801
-    2
------
  3799

  3801      45
-    2    + 43
------    ----
  3799      88

  3801      45      123
-    2    + 43    +  49
------    ----    -----
  3799      88      172

FError: Numbers must only contain digits.
  3801
-    2
------
  3799

  3801      45
-    2    + 43
------    ----
  3799      88

  3801      45      123
-    2    + 43    +  49
------    ----    -----
  3799      88      172

F   32
- 698
-----
 -666

   32         1
- 698    - 3801
-----    ------
 -666     -3800

   32         1      45
- 698    - 3801    + 43
-----    ------    ----
 -666     -3800      88

   32         1      45      123
- 698    - 3801    + 43    +  49
-----    ------    ----    -----
 -666     -3800      88      172

FError: Numbers cannot be more than four digits.
  3801
-    2
------
  3799

  3801      45
-    2    + 43
------    ----
  3799      88

  3801      45      123
-    2    + 43    +  49
------    ----    -----
  3799      88      172

FError: Too many problems.
F

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Challenge: Arithmetic Formatter

Link to the challenge:

freeCodeCamp.org

[JeremyLT]

The Fs indicate that you have test suite failures.

@aroddoet

print(string)

You are not actually returning this variable, so you are returning the default value of None. (print is not the same thing as return).

Also, I wouldn’t name any variable string. It is best not to name variables after types(integer, int, string, bool, etc), even in Python, which lets you use pretty bad variable names.

[aroddoet]

Thank you for the answer!
I tried changing the print statements to return but I’m still getting error on the test_arrangement and test_sollutions and still getting a none. Now I have no idea what did wrong again, and everything is vertical, but it’s at least less error messages?

   32
+ 698
-----
  730
None
    3
+ 855
-----
  858
F..   32
- 698
-----
 -666
F..

[JeremyLT]

It looks like you are returning too early now. You should only return outside of your loop over all problems.

[aroddoet]

Thank you again!
I’m still getting an error on test_arrangement. It appears to be expecting a different first operation than the one on the output? It seems to expected 3 + 855 instead of 32 + 698, or am I reading it wrong? Am I somehow giving out the wrong operation?how???

   32      3801      45      123
+ 698    -    2    + 43    +  49
-----    ------    ----    -----
  730      3799      88      172
F.....
======================================================================
FAIL: test_arrangement (test_module.UnitTests)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/runner/boilerplate-arithmetic-formatter-6/test_module.py", line 10, in test_arrangement
    self.assertEqual(actual, expected, 'Expected different output when calling "arithmetic_arranger()" with ["3 + 855", "3801 - 2", "45 + 43", "123 + 49"]')
AssertionError: '    [68 chars]-    ------    ----    -----\n  858      3799      88      172' != '    [68 chars]-    ------    ----    -----'
      3      3801      45      123
  + 855    -    2    + 43    +  49
- -----    ------    ----    -----
?                                 -
+ -----    ------    ----    ------   858      3799      88      172 : Expected different output when calling "arithmetic_arranger()" with ["3 + 855", "3801 - 2", "45 + 43", "123 + 49"]

[JeremyLT]

You seem to be adding the solutions row when it wasn’t requested.