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

Posted by Keifer Dalton
Keifer Dalton
3,488 Points

Swift Loops

"Now that we have the while loop set up, it's time to compute the sum! Using the value of counter as an index value, retrieve each value from the array and add it to the value of sum.

For example: sum = sum + newValue. Or you could use the compound addition operator sum += newValue where newValue is the value retrieved from the array."

I don't think it goes over this in the Loop section of Swift. I rewatched the videos multiple times and could not figure this out!

loops.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(numbers[counter])
  counter += 1


}

1 Answer

Steve Hunter
Steve Hunter
57,712 Points

Hi Keifer,

You're nearly there. Your while loop is spot on - good work.

Inside the while loop you want to access the numbers array and add each element of that array into the sum variable one by one. That's what the loop gets you access to. You can use numbers[counter] to access the value held in each array element. Add that into the cumulative value held in sum using +=.

Something like:

while counter < numbers.count {
  sum += numbers[counter]
  counter += 1
}

Make sense?

Steve.