Adding items in a list

Question

My code here doesn't seem to add up the items in the list. I got it before, and now I cant seem to duplicate what I did last time. Any ideas?

functions.py

# 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 (x):
  sum = 0
  for item in x:
    sum = sum + x
  return sum

Answer 1 · 2015-01-25T19:36:13Z

January 25, 2015 7:36pm

item is an individual element, and x is the entire list. Switch to this:

def add_list (x):
  sum = 0
  for item in x:
    sum = sum + item
  return sum

Answer 2 · 2015-01-25T19:38:02Z

January 25, 2015 7:38pm

Hi Ben,

When adjusting the values of your sum variable, instead of adding sum to x, you can use the += operator.

sum += x

Also, you can't add x to the sum variable, because x is the list the challenge is going to pass to your function. Instead you will want to use your item from your for loop, because it will be each number from your list. For example:

The task will pass you a list that will resemble this

[12, 45, 23, 4, 189]

and then you're for loop will loop over every number and that number can be referred to as item or whatever you decided to call it.

for item in x:
  print(item)

The first time the loop runs item will be equal to 12, the second time it will be equal to 45, ect...

def add_list (x):
  sum = 0
  for item in x: # Item will be each number from your list
    sum += item # += Operator to add the item to the sum variable
  return sum

I hope this helped. If you have any other question don't hesitate to ask.

Ozzie

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Ben Muresan

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Adding items in a list

2 Answers

Dan Johnson

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