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iOS Swift 2.0 Collections and Control Flow Control Flow With Loops While and Repeat While

Posted by Jacob Carroll
Jacob Carroll
5,957 Points

Part 2 out of 2 of Code Challenge: Working with Loops

I have been doing the code challenge and have got to the last step.

while counter > numbers.count { counter++ }

How do you :Use the value of counter as an index value, retrieve each value from the array and add it to the value of sum.

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

All help with this would be appreciated.

2 Answers

David Lin
David Lin
35,864 Points
David Lin
David Lin
35,864 Points 
let numbers = [2,8,1,16,4,3,9] 
var sum = 0 
var counter= 0

while counter < numbers.count { 
 sum += numbers[counter++] 
}
Fadi Yas
Fadi Yas
1,110 Points
Fadi Yas
Fadi Yas
1,110 Points

This is for Swift 2...

If I were to do 

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

while counter < numbers.count { 

 sum += numbers[counter += 1] 

}

it would throw an error still...

Jacob Carroll
Jacob Carroll
5,957 Points

Thanks for this as I found my mistake.

Andrew Doumith
Andrew Doumith
1,392 Points
Andrew Doumith
Andrew Doumith
1,392 Points

Hey everyone.

This is literally driving me crazy. I know everything is corrent, why am I getting this error??

////// Exercise ///////

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 += 1]

}

I'm getting an error under sum += numbers[counter += 1] that is saying "Cannot subscript a value of type ['int'] with an index of type '()'

Please help!