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

Posted by Landon Hale
Landon Hale
1,203 Points

How to continue without using a for in loop

I am not sure how I would be able to retrieve the next numbers down the array without using a for loop since you are not able to add 1 to the array to increase the index value within the while loop. Without that increase, I cannot find the sum of these numbers. Please help me with this solution.

loops.swift 
/*
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.
*/

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

// Enter your code below

while counter < numbers.count {  
  sum += numbers[0]
  counter += 1
}

1 Answer

Matthew Connolly
seal-mask
.a{fill-rule:evenodd;}techdegree
Matthew Connolly
iOS Development Techdegree Student 11,595 Points
Matthew Connolly
.a{fill-rule:evenodd;}techdegree
Matthew Connolly
iOS Development Techdegree Student 11,595 Points

Hi Landon,

You are already incrementing a value in your code (your counter variable). Maybe that can help you move through your numbers array.

Landon Hale
Landon Hale
1,203 Points

Thanks Matthew Connolly, I got it now!