Build an Arithmetic Formatter Project - Build an Arithmetic Formatter Project

Python
1

Tell us what’s happening:

Hello! Could you please help me?
The details of the problem:
When I run the tests, the tests whose outputs are supposed to be Error messages pass the test. But, the remaining tests, where correct values are inputted, they fail the test. I have spent a lot of time looking for errors in my code, and as well as manually checking the expected test output, and my test output; and run the tests again, but they don’t pass the test. Hence, could you please check ad let me know what is wrong with it?

My code so far:

def arithmetic_arranger(problems, show_answers=False):
    if len(problems)>5:
        return 'Error: Too many problems.'

    operands1=''
    line2=''
    lines=''
    answers=''

    for problem in problems:

        operand1=problem.split(' ')[0]
        operator = problem.split(' ')[1]
        operand2= problem.split(' ')[2]

        if operator != '+' and operator != '-':
            return "Error: Operator must be '+' or '-'."

        if not(operand1.isdigit() and operand2.isdigit()):
            return 'Error: Numbers must only contain digits.'

        if len(operand1)>4 or len(operand2)>4:
            return 'Error: Numbers cannot be more than four digits.'

        

        
        line=''
        if operator=='+':
            answer = str(int(operand1) + int(operand2))
        elif operator=='-':
            answer = str(int(operand1) - int(operand2))

        
        width = max(len(operand1), len(operand2))+2


        if problem!=problems[-1]:
            operands1 += str(operand1).rjust(width)+'      '
            line2 += operator+str(operand2).rjust(width-1)+'      '
            lines += '-'*width +'      '
            answers += str(answer).rjust(width)+'      '

        else:
            operands1 += str(operand1).rjust(width)
            line2 += operator+str(operand2).rjust(width-1)
            lines += '-'*width
            answers += str(answer).rjust(width)




    if show_answers==True:
        arranged=operands1 + '\n' + line2 + '\n' + lines + '\n' + answers

    elif show_answers==False:
        arranged=operands1 + '\n' + line2 + '\n' + lines
    
    return arranged

print(f'\n{arithmetic_arranger(["32 - 698", "1 - 3801", "45 + 43", "123 + 49", "988 + 40"], True)}')

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/128.0.0.0 Safari/537.36 Edg/128.0.0.0

Challenge Information:

Build an Arithmetic Formatter Project - Build an Arithmetic Formatter Project

2

There’s a note at the end of the instructions but it’s easy to miss:

Note: open the browser console with F12 to see a more verbose output of the tests.

Also helps to use repr() to print your function so you can compare the output with the tests format:

print(repr(arithmetic_arranger(["3801 - 2", "123 + 49"])))
3

I opened the Developer Tools, but I have just started, and thus couldn’t make out anything from it. There were a lot of issues it showed, like 99+ it showed

4

And as for using repr(), the output was all jumbled up, none of it made sense

5

Show me.

It should match the test output:
arithmetic_arranger(["3801 - 2", "123 + 49"]) should return 3801 123\n- 2 + 49\n------ -----

print(repr(arithmetic_arranger(["3801 - 2", "123 + 49"])))

' 3801 123\n- 2 + 49\n------ -----'

This shows the string with the formatting characters like space and \n clearly so you can compare.

`  3801      123\n-    2    +  49\n------    -----`
'  3801        123\n-    2      +  49\n------      -----'

You can see that you have too many spaces between 3801 and 123.

6

As for the console output it can be a mess to parse at first, but look for the assertion error and diff output.

The assertion error and diff gives you a lot of information to track down a problem. For example:

AssertionError: 'Year' != 'Years'
- Year
+ Years
?     +

Your output comes first, and the output that the test expects is second.

AssertionError: ‘Year’ != ‘Years’

Your output: Year does not equal what’s expected: Years

This is called a diff, and it shows you the differences between two files or blocks of code:

- Year
+ Years
?     +

- Dash indicates the incorrect output
+ Plus shows what it should be
? The Question mark line indicates the place of the character that’s different between the two lines. Here a + is placed under the missing s .

Here’s another example:

E       AssertionError: Expected different output when calling "arithmetic_arranger()" with ["3801 - 2", "123 + 49"]
E       assert '  3801      123    \n   - 2     + 49    \n------    -----    \n' == '  3801      123\n-    2    +  49\n------    -----'
E         -   3801      123
E         +   3801      123    
E         ?                ++++
E         - -    2    +  49
E         +    - 2     + 49    
E         - ------    -----
E         + ------    -----    
E         ?                +++++

The first line is long, and it helps to view it as 2 lines in fixed width characters, so you can compare it character by character:

'  3801      123    \n   - 2     + 49    \n------    -----    \n'
'  3801      123\n-    2    +  49\n------    -----'

Again, your output is first and the expected output is second. Here it’s easy to see extra spaces or \n characters.

E         -   3801      123
E         +   3801      123    
E         ?                ++++

Here the ? line indicates 4 extra spaces at the end of a line using four + symbols. Spaces are a little difficult to see this way, so it’s useful to use both formats together.

I hope this helps interpret your error!

7

So like for this, in the tests, each test expect different no. of spaces, so could you please help me with that in my code?

For example:
In the test,

arithmetic_arranger(["3801 - 2", "123 + 49"])` should return 
`  3801      123\n-    2    +  49\n------    -----

There are 6 spaces,

But in another test,

arithmetic_arranger(["1 + 2", "1 - 9380"])` should return 
`  1         1\n+ 2    - 9380\n---    ------

There are 9 spaces… so could you please help me with this?

8

This exercise suggests opening the browser console to view the detailed output from the tests. Have you tried this?

Edit: reading your older post I see that you did try but you don’t know how to interpret the result. But you’ve already received some comments above that should help you with that as well.

9

This should be apparent to you since your function works in a similar way. There are more spaces between 1s because 1 is only 1 character and 123 is 3 characters so it maintains a fixed distance between equations.

Your code also maintains a fixed distance between equations:

   32           1        45        123        988
- 698      - 3801      + 43      +  49      +  40
-----      ------      ----      -----      -----

You have 6 spaces between each set of ---

Look at the example in the instructions:

   32      3801      45      123
+ 698    -    2    + 43    +  49
-----    ------    ----    -----

Only 4 spaces between each set of ---.

Compare your output carefully with the output the test requires: