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

Posted by Craig Talma
Craig Talma
1,964 Points

I got the answer of the forums and honestly have no Idea why this is the answer. Can anyone please explain?

I guess I am confused as to what the variables are for. And what the variables doing in relation to each other inside the code and why they are referencing each other.

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

// Enter your code belowwhile counter < numbers.count {
    var newValue = numbers[counter]
    sum += newValue
    counter++
}

1 Answer

Paul Brazell
Paul Brazell
14,371 Points
Paul Brazell
Paul Brazell
14,371 Points

It doesn't look like you need the newValue variable.

here is a more simplified solution using a while loop

numbers is the array of numbers you are working with counter is whats used to identify what iteration of the loop you are currently in sum is self explanatory

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

// Cycle through the numbers array and sum its values

while counter < numbers.count {
    sum += numbers[counter]
    counter++  // or counter += 1 (increment and decrement operators are going away in swift 3.0)
}