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![Wardah M](https://secure.gravatar.com/avatar/327ecf1104febe4dc550c6a8300d8c62?s=96&d=https%3A%2F%2Fecs-static.teamtreehouse.com%2Fassets%2Fcontent%2Fdefault_avatar-445fbbabfc8dc9188fb5967fe43322ee0c3e0dd1e10f378bf8343784af5a13eb.webp&r=pg)
Wardah M
477 PointsStuck on challenge question.. Very confusing
I dont understand this whole while loop thing. It would be great if someone could explain it to me in easier words. Also the challenge question asks for "Now that we have the while loop set up, it's time to compute the sum! Using the value of counter as an index value, retrieve each value from the array and add it to the value of sum. For example: sum = sum + newValue. Or you could use the compound addition operator sum += newValue where newValue is the value retrieved from the array.
AND THIS IS WHAT I DID....
let numbers = [2,8,1,16,4,3,9] var sum = 0 var counter = 0
// Enter your code below
while counter < numbers.count { sum = sum + numbers[counter]
counter++
}
sum = sum + 6
It is showing an error. PLEASE HELP.
let numbers = [2,8,1,16,4,3,9]
var sum = 0
var counter = 0
// Enter your code below
while counter < numbers.count {
sum = sum + numbers[counter]
counter++
}
sum = sum + 6
2 Answers
![jcorum](https://uploads.teamtreehouse.com/production/profile-photos/4188262/micro_jgc_photo.jpg)
jcorum
71,830 PointsWardah, your loop is fine. The editor just doesn't like the last line. So delete sum = sum + 6 and you're good to go.
![jcorum](https://uploads.teamtreehouse.com/production/profile-photos/4188262/micro_jgc_photo.jpg)
jcorum
71,830 PointsWardah, as I indicated earlier, your current code works fine for both tasks in the challenge as long as you remove the line sum = sum + 6 at the end.
The line of code that task 2 wants: sum = sum + numbers[counter], you already have. Note that you can also write this way: sum += numbers[counter], as the challenge indicates. The second is just shorthand for the first.
Wardah M
477 PointsWardah M
477 Pointsbut how am I supposed to do this step?
Now that we have the while loop set up, it's time to compute the sum! Using the value of counter as an index value, retrieve each value from the array and add it to the value of sum.
For example: sum = sum + newValue. Or you could use the compound addition operator sum += newValue where newValue is the value retrieved from the array.