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

Mac Stringer
Mac Stringer
461 Points

Help with the While Loop challenge

For the life of me, I cannot figure out why this code doesn't work.

Why can't I use;

while counter < 7 {
counter += 1 }?

I keep getting the error that says I'm not doing the counter correctly.

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

// Enter your code below
while counter < 7 {
  counter =+ 1
  numbers[counter] + sum = sum

1 Answer

Jhoan Arango
Jhoan Arango
14,575 Points

Hello Mac:

So the challenge wants you to do a while loop, and to increment the counter as long as it's less than the number of items in the array.

We know that we can use the .count property the array has so that we know how many items it holds. We want the loop to say something like " while counter is less than the items in the array, then loop once and add one to the counter".

Here is how that will look like.

// Swift 2.0

while counter < numbers.count {

// Swift 3.0 

while counter < numbers.count {
  counter += 1

Good luck and hope this helps.