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Python

Itsa Snake
Itsa Snake
3,852 Points
Posted by Itsa Snake
Itsa Snake
3,852 Points

Concatenating - correct use of converting int to str?

Hello,

I am doing this task and have figured out how to pass it.

The goal is to strip out all the text from a list, then add all the figures together, then combine the two.

While trying to code it, I kept getting this error on line 10: TypeError: can only concatenate str (not "int") to str

My fix was therefore to convert the return_num (int or float) into a str before calling combining it.

I'd be interested in how a pro would code the below. I feel like i've done an amateur workaround. 

def combiner(the_list):
    return_text = ""
    return_num = 0
    for item in the_list:
        if isinstance(item, (int, float)):
            return_num = return_num + item
        elif isinstance(item, str):
            return_text = return_text + item

    return return_text+str(return_num)

my_list = ["silly", "bun", 1, 2, 3]
print(combiner(my_list))

2 Answers

ygh5254e69hy5h545uj56592yh5j94595682hy95
ygh5254e69hy5h545uj56592yh5j94595682hy95
7,934 Points
ygh5254e69hy5h545uj56592yh5j94595682hy95
ygh5254e69hy5h545uj56592yh5j94595682hy95
7,934 Points
  • I would not say that I'm a "PRO", but this is how I would solve this challenge
def combiner(listOfWordsAndNumber):

    return_num = [itemInList for itemInList in listOfWordsAndNumber if isinstance(itemInList, (int, float))]
    return_text = [itemInList for itemInList in listOfWordsAndNumber if isinstance(itemInList, (str))]

    return ''.join(return_text) + str(sum(return_num))

my_list = ["silly", "bun", 1, 2, 3]
print(combiner(my_list))
Sergey Arestov
Sergey Arestov
7,601 Points
Sergey Arestov
Sergey Arestov
7,601 Points

And this code is the answer. But can you please tell me what's the difference with mine (that wasn't correct ("Didn't get the expected output")):

def combiner(arg):
    word = ""
    num = 0
    nfl = 0
    for each in arg:
        if isinstance (each, str):
            word += each
        elif isinstance (each, int):
            num += each
        elif isinstance (each, float):
            nfl += each
    num = num + nfl
    output = word + str(num)
    return output
ygh5254e69hy5h545uj56592yh5j94595682hy95
ygh5254e69hy5h545uj56592yh5j94595682hy95
7,934 Points
ygh5254e69hy5h545uj56592yh5j94595682hy95
ygh5254e69hy5h545uj56592yh5j94595682hy95
7,934 Points 
# It works fine when I use it locally. I guess TreeHouse wants you to use isinstance(each, (int, float)), like this
def combiner(arg):
    word = ""
    num = 0
    for each in arg:
        if isinstance (each, str):
            word += each
        elif isinstance (each, (int, float)):
            num += each
    output = word + str(num)
    return output