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Gregory Heard
1,975 PointsWhy isn't this working? It returns correctly locally.
This works. Why is the code challenge not completing?
# combo([1, 2, 3], 'abc')
# Output:
# [(1, 'a'), (2, 'b'), (3, 'c')]
# If you use .append(), you'll want to pass it a tuple of new values.
def combo (a, b):
c = []
for i in a:
c.append((i, b[i-1]))
return(c)
6 Answers
Jennifer Nordell
Treehouse TeacherJeremy is correct. The challenge explictly asks for a list to be returned. Not an array, which is what you're currently returning. But even if we fix that, it still doesn't work. And that's because you need for i in a range. I rewrote your solution. Hope this helps!
def combo(a, b):
c = list()
for i in range(len(a)):
c.append((a[i], b[i]))
return c
Jeremy Hill
29,567 PointsEven though the code may work on your machine it may not be the output that the challenge is looking for or the way that you coded it. They usually check for consistency with the way that they are teaching you.
Gregory Heard
1,975 PointsI have gone through it with an experienced programmer i work with, and he can't understand why it isn't working either. That's the thing.
Cindy Lea
Courses Plus Student 6,497 PointsIt says your string index is out of range. Even if it works locally, doesnt mean it works for the challenge. If your code isnt what the challenge is looking for, it will be wrong.
Gregory Heard
1,975 PointsOK. Could I have some suggestions on what it could be? I am completing it to the specification that is being described.
Thanks!
Cindy Lea
Courses Plus Student 6,497 PointsHere is 1 way to do it (it passes the challenge:
my_list = [] def combo(list, str): #x = 0 for idx, value in enumerate(str): b = value a = list[idx] c = a, b my_list.append(c) #x = x + 1 continue #print(my_list)
return my_list
Gregory Heard
1,975 PointsGregory Heard
1,975 PointsHi Jennifer,
Thanks a lot!
Only one thing though, i thought you initiliase an empty list with [] ? What's the difference between that and list(). Also what does the range(len()) do?
Appreciate the help!