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

Erik Faye Karla
Erik Faye Karla
1,523 Points

Code challenge While Loop doesn't work!

so when I try doing this code challenge in Collections and Control, I get this error message: swift_lint.swift:10:16: error: use of unresolved identifier 'index' sum += numbers[index]

When I try the exact same in my xcode playground it works perfectly and gives me the right sum! the sum of the numbers in the array is 43 and that what I get with the code inside xcode! thx in forhand

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{

sum += numbers[index]
counter++
}

2 Answers

Marina Alenskaja
Marina Alenskaja
9,320 Points

Hi!

The error is in the "index" that you are using to access the numbers in the array. You should replace "index" with the "counter". The counter will start with 0 (the first item in the array), and then your while loop increments it by 1 each time the loop runs.

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[index]
counter++
}

´´´
Erik Faye Karla
Erik Faye Karla
1,523 Points

thank you! it worked now!