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Ahmed Hallajian
824 PointsAfter writing, 'for item in list:', how do I make the program add up the numbers inside the list?
Do I need to have made my own list beforehand?
# 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):
for item in list:
1 Answer
Matthew Rigdon
8,223 PointsThis question assumes a list is already made. You can imagine using [1, 2, 3] like in the comments.
def add_list(list):
sum = 0
for item in list:
sum += item
For item in list will take each value in the list (1, 2, and 3) and cycle through that code. So the first time through it will select "1" as the item, and then it will add that to sum. Next, it will take "2" as the item, and add that to sum (where sum already is = 1 from the previous iteration).
If you want to visualize this, copy/paste this code into (www.pythontutor.com) .
def add_list(list):
sum = 0
for item in list:
sum += item
return sum
add_list([1,2,3])