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

Posted by Lorenz Miranda
Lorenz Miranda
786 Points

While Loops Code Challenge

I dont’t understand how to solve the second part of the while loop code Challenge

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 = sum + newValue
}

1 Answer

Matthew Long
Matthew Long
28,407 Points
Matthew Long
Matthew Long
28,407 Points

Looks like the way the challenge was worded has thrown you off. That sum += newValue bit was only meant as an example. That's not a solution.

You want to add each number from the numbers array using the counter as the index. So numbers[0] (when the counter is 0) would be the first value in the numbers array, 2. This is when you add it to the sum variable using that sum += newValue demonstration in the challenge description. It would look like sum += numbers[counter] in this case.

Also, make sure to have the counter incrementing afterward because you would be skipping over the first index value if not. 

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

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