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Python

Posted by Gerard Nwazk
Gerard Nwazk
Courses Plus Student 2,833 Points

What am i not doing right here? pls correct me!...

Challenge Task 1 of 1

Alright, here's a fun task! Create a function named combiner that takes a single argument, which will be a list made up of strings and numbers. Return a single string that is a combination of all of the strings in the list and then the sum of all of the numbers. For example, with the input ["apple", 5.2, "dog", 8], combiner would return "appledog13.2". Be sure to use isinstance to solve this as I might try to trick you.

Am i doing it right or am i missing somthing?

instances.py 
# input argument
# list to contain arguments
# loop through the list
# if the list isinstance(str)
# if the list isinstance(int)
# return arg_list

def combiner(args):
    arg_list = []

    string_arg = []
    string_arg.append(args)

    int_arg = []
    int_arg.append(args)

    if arg_list:

        for arg_str in arg_list:
            if isinstance(arg_str, str):
                return string_arg.append(arg_str)

        for arg_int in arg_list:
            if isinstance(arg_int, int):
                return int_arg.append(arg_int)

        return arg_list.extend(string_arg, int_arg)

3 Answers

Steven Parker
Steven Parker
231,275 Points
Steven Parker
Steven Parker
231,275 Points

Here's a few hints:

  • you may not want to append the entire "args" list to both new sub-lists
  • you might want to put something into arg_list before testing it, an empty list is always "falsey"
  • you might want to check all the items in the list before returning
  • you're testing for int and str values, but what about float?
  • you still need to combine numbers by adding them
Unsubscribed User
Unsubscribed User
3,284 Points
Unsubscribed User
Unsubscribed User
3,284 Points

You don't really need to create two new lists and do if arg_list. Instead, it might be easier to tackle this problem if you turn the input into a list or just except the input's gonna be a list, since you and I already know it's gonna be a list. Then just loop through the list, and check if it's a string or an integer or a float. maybe you could define a global variable to concatenate the strings and increment the numbers, and then just combine the two in the end.

However, you can still go with this approach though. To me, it makes sense if you, in the beginning, append args into your new list and check if that list has any item inside it. and loop through that list and have two if statements instead of two for loops.

Leroy Saldanha
Leroy Saldanha
8,006 Points
Leroy Saldanha
Leroy Saldanha
8,006 Points

def combiner(single): give_back=[] add_numbers = 0 for x in single: if isinstance(x,(int,float)): add_numbers += x if isinstance(x,(str)): give_back.append(x) give_back.append(str(add_numbers)) return ''.join(give_back)