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

Makan F
Makan F
9,434 Points

having some trouble here

Much appreciated

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

// Enter your code below

while counter < numbers.count {

sum += 

2 Answers

Hi Manny,

I found two issues in the code sample you provided:

  1. The sum statement is sitting outside of the scope of the while loop, so it is only executed once. Assuming you want sum to be changed each time the loop runs, it should be contained inside the loop.
  2. The sum += expression is missing whatever value you'd like to add. Assuming you want to add the value of each item in the numbers array, you can use subscript syntax with the variable counter as the item index.

Here's a code sample that resolves both issues and compiles successfully:

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

I hope this helps!

Paul Brazell
Paul Brazell
14,371 Points

Just want to mark this case as answered. David has a perfect answer here, but he just put it in as a comment!

Ha! I totally overlooked the Add a Comment section when responding. Thanks for the heads up!