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

keep getting this error " ++ is unavailable: it has been removed from swift 3

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

keep getting the error "++ is unavailable

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 {
  counter += 1
   sum += numbers[counter]
   counter++
}

2 Answers

andren
andren
28,558 Points

That message is accurate. The ++ operator was removed in Swift 3, and since you use it in the last line of your loop your code won't run. You don't really need that line though as you are already increment counter with += 1 at the top of the loop which is a valid way of increment in Swift 3.

You shouldn't increment it at the start of the loop though, but at the end, since counter is used to pull items out of the numbers array.

If you remove your last line and move the first line down like this:

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

Then your code will work perfectly fine.