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Alec Burmeister
1,627 Pointsfunctions challenge - stuck on first task
I can't really think of another way to word the code to receive the correct sum. I was able to somehow pass the first task with another code, but I was receiving an incorrect sum.
The error: list index out of range.
# add_list([1, 2, 3]) should return 6
# summarize([1, 2, 3]) should return "The sum of [1, 2, 3] is 6."
# Note: both functions will only take *one* argument each.
def add_list(list):
total = 0
for i in list:
total += list[i]
return total
2 Answers
deckey
14,630 PointsHi Alec, the function was correctly set, but you are calling list[i] within the loop, which is wrong.
- first loop pass, i = 1, so list[1] gets called - total becomes 2
- second pass, i = 2, so list[2] gets called - total becomes 5
- third pass, i =3 , so list[3] gets called which is 'out of index' as there are only 3 elements in the list.
So, what you need is just 'i' to be added to total, not list[i]
good luck!
Kenneth Love
Treehouse Guest TeacherYou don't need list[i] when you do for i in list:. i is the current item for this step in the list. Look at this:
my_list = ['a', 'b', 'c']
for letter in my_list:
print(letter)
This would print
a
b
c
because each time the loop loops, letter is changed to the next item in my_list.
Alec Burmeister
1,627 PointsThank you for explaining it in such a simple way there. It makes a lot of sense!