code challenge

Question

Am I close to the answer?
```instances.py
def combiner(lista):
lista = ["7amada", 81 , "rollers", 5.6]
for i in lista:
    if isinstance(i , (str, int , float)):
    print(i.join(str, int, float))
```

Dane Parchment · Accepted Answer

No, unfortunately you are not close to solving this problem, so to alleviate that, why don't we solve this together?
The instructions ask us to create a function called combiner that will take a list as a parameter:
python
def combiner(the_list):
     pass

Then we are told how to solve the problem: Namely we need to iterate through each item within the list and depending on it's type we have to either append it to a string or add it to a number. So let's begin setting that up:
python
def combiner(the_list):
  sum_of = 0;
  str_of = ""

So above what we do is create two important variables: sum_of and str_of. These two variables will store the sum of all of the numbers within the list and the combined strings of the list respectively. Now we need to iterate through the list and access each item, we can easily do that with a for in loop.
python
def combiner(l):
  sum_of = 0;
  str_of = ""
  for item in l:

Now that we are iterating through each list item referencing each item as item we can now check if said item is of a number or string type!
python
def combiner(l):
  sum_of = 0;
  str_of = ""
  for item in l:
    if(isinstance(item, str)): 
      str_of += item

First we check and see if it is of type str (or string) and if so we add it to our empty string from earlier, then moving to the next item! Now we can check if the item is of a number type: int, long, float, complex and if so add it to our sum_of variable.
python
def combiner(l):
  sum_of = 0;
  str_of = ""
  for item in l:
    if(isinstance(item, str)): 
      str_of += item
    if(isinstance(item,(int, float, complex))):
      sum_of += item

That's it! Now we can just return the combined string and sum together and return it!
python
def combiner(l):
  sum_of = 0;
  str_of = ""
  for item in l:
    if(isinstance(item, str)): 
      str_of += item
    if(isinstance(item,(int, float, complex))):
      sum_of += item
  return "{}{}".format(str_of, sum_of)

There is of course a fatal flaw of this program but it will work regardless! (Hint: the fatal flaw has to do with the fact that this program will always assume that their are numbers in the list, what do you think it will do wrong if there are no numbers in the list?)

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Hussein Amr

Hussein Amr

code challenge

1 Answer

Dane Parchment

Dane Parchment

Hussein Amr

Hussein Amr