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

Amit Ahuja
Amit Ahuja
706 Points
Posted by Amit Ahuja
Amit Ahuja
706 Points

Control Flow: Computing from Arrays

I tried putting it on playgrounds and it won't add properly. The goal is to add all the numbers from the array together using a while loop. Also, it says that the index is out of range, not sure why because counter < numbers.count

Thanks in advance.

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 {
print(sum)
counter++
sum = numbers[Counter] + sum

}
Amit Ahuja
Amit Ahuja
706 Points
Amit Ahuja
Amit Ahuja
706 Points

Just noticed i messed up the spelling of "counter" using a capital "C" but that still wouldn't fix it.

1 Answer

Jennifer Nordell
seal-mask
STAFF
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Jennifer Nordell
Treehouse Teacher
Jennifer Nordell
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher

First, your increment of counter should come after you first add the sum of the first element to the running total of sum. Otherwise you begin at the number at the index of 1 instead of the index of 0. Keep in mind that if they don't ask you to print something in a challenge, you shouldn't. Here's my code. Hope it clarifies things!

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++
}