Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

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

Posted by Jazil Zaim
Jazil Zaim
8,502 Points

How do I solve this?

I am supposed to retrieve each value from the array and add it to the value of sum.

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

// Enter your code below

while counter < numbers.count {
     var newValue = counter + sum 
     sum = sum + newValue
      counter += 1
      print(numbers[count])
}

1 Answer

Dan Lindsay
Dan Lindsay
39,611 Points
Dan Lindsay
Dan Lindsay
39,611 Points

Hey Jazil,

Use the counter value as the index value of the numbers array, then assign that to your new value. You don't need the print statement either. Just this:

while counter < numbers.count {
  var newValue = numbers[counter]
  sum += newValue
  counter += 1

}

First time through the loop, counter equals 0, so numbers[counter] will be 2 the first time through. End of the loop we increment counter by one, so the second time through numbers[counter] will be 8, and so on.

Hope this helps!