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iOS Swift 2.0 Collections and Control Flow Control Flow With Loops Working with Loops

Farbod Salman
Farbod Salman
1,061 Points
Posted by Farbod Salman
Farbod Salman
1,061 Points

I cannot figure this question out!

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.

***Any help and explanations would be much appreciated. Thanks!

while.swift 
let numbers = [2,8,1,16,4,3,9]
var sum = 0
var counter = 0

// Enter your code below

while counter < numbers.count{

counter++
}

while(counter < numbers.count){
  sum += numbers[counter]
  counter++
}

2 Answers

jcorum
jcorum
71,830 Points

It looks like your only problem is that you have two loops, rather than one, and the first is incomplete. I suggest you just delete it. As this works fine:

let numbers = [2,8,1,16,4,3,9]
var sum = 0
var counter = 0

// Enter your code below
while (counter < numbers.count) {
  sum += numbers[counter]
  counter++
}

It's interesting that the challenge won't accept counter += 1, although Swift is moving away from ++ in the next version.

Farbod Salman
Farbod Salman
1,061 Points
Farbod Salman
Farbod Salman
1,061 Points

Oh yes thank you! Seemed like a dumb mistake. I love treehouse but some of their code challenges are not well put together at all. It tells you that you need to keep all the code you have written from task one in every task but in this one you need to delete the first one that you created. Very confusing. Thanks!