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

While loop

I'm trying to compute the sum of an array of numbers using a while loop. The task is to use 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.

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 {
      sum += counter
      counter += 1
}

1 Answer

Hello, Idris.

When I was working on this, I had the same issue. What I changed was this line of code:

sum += counter

to:

sum += numbers[counter] or sum = sum + numbers[counter].

The reason being the addition of the numbers, and you are going through each one through counter. If you need more clarification, I am happy to help.