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chikangsong
755 PointsI do not have any idea to pass Challenge Task 1 of stage5 - function.
I coded like this but it is wrong? why? how to solve it using by a 'for' loop and 1 arguments??
# 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.
function_list = [1, 2, 3]
def add_list():
return function_list[0]+function_list[1]+function_list[2]
def summarize():
print ("The sum of {} is {}.".format(function_list, add_list()))
1 Answer
Dan Johnson
40,533 PointsSince your function could be given a list of any length (the list in the comments is just an example), you can't use hard coded indexes to add everything up. That's why you use a for loop to pull out each element:
def add_list(numbers):
# Running total. Start out at 0
sum = 0
# For every number in the list passed in
# Update the sum
for number in numbers:
sum += number
return sum
chikangsong
755 PointsThank you for the comments. I coded as same and try it with 'add_list(6)'. However, I got an error as "TypeError: 'int' object is not iterable".
What am I wrong?
Dan Johnson
40,533 Points6 is an int, so you can't iterate over it (it's not a container/collection of elements). You could do [6] if you wanted.
If this is for the challenge, you don't have to supply the arguments or anything. It'll check the function for you.
chikangsong
755 PointsI made it! Thanks
chikangsong
755 Pointschikangsong
755 PointsThis is the Task description.
Make a function named add_list that takes a list. The function should then add all of the items in the list together and return the total. Assume the list contains only numbers. You'll probably want to use a for loop. You will not need to use input().