**Tell us what’s happening:**

When running the program checker for my project I am passing 8 of the 10 sets, but for some reason two of the sets incorrectly calculate the operation. This only occurs when I am running the program on the replit program not on my own IDE. As far as I can tell from the bug report my program is outputting an inverted operator (switching from + to - or vice versa). If I manually input the list it will give me the correct numbers as well. Any help on what could be causing this would be greatly appreciated!

Below are the tests I am still failing:

```
E - 3800 88 172 1028
E + 3800 2 74 948
E - 858 1028
E + -852 948
```

**Your code so far**

```
def arithmetic_arranger(problems, display_results=False):
topl = ''
midl = ''
linel = ''
outputl = ''
if len(problems) > 5:
return "Error: Too many problems."
else:
lproblems = [problem.split(" ") for problem in problems]
for problem in lproblems:
if "*" in problem or "/" in problem:
return "Error: Operator must be '+' or '-'."
elif problem[0].isnumeric() is False or problem[-1].isnumeric() is False:
return "Error: Numbers must only contain digits."
elif len(problem[0]) > 4 or len(problem[-1]) > 4:
return "Error: Numbers cannot be more than four digits."
else:
if problem[1] == "+":
output = int(problem[0]) + int(problem[-1])
else:
output = int(problem[0]) - int(problem[-1])
width = max(len(problem[0]), len(problem[-1]))+2
topl += problem[0].rjust(width).rstrip() + " "
midl += problem[1] + problem[-1].rjust(width-1).rstrip() + " "
linel += ("-" * width) + " "
outputl += str(output).rjust(width) + " "
if display_results is True:
arranged_problems = topl.rstrip()+"\n"+midl.rstrip()+"\n"+linel.rstrip()+"\n"+outputl.rstrip()
else:
arranged_problems = topl.rstrip()+"\n"+midl.rstrip()+"\n"+linel.rstrip()
return arranged_problems
```

https://replit.com/@Ochem92/boilerplate-arithmetic-formatter-1#arithmetic_arranger.py

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**Challenge:** Arithmetic Formatter

**Link to the challenge:**