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

Kyle Deckert
Kyle Deckert
875 Points

Stuck on While Counter

Stuck on Challenge for while and sum of the while loop. Not too sure of how to terminate without crashing as it keeps calculating. Not too sure of what I am doing wrong. Was wondering if anyone had any insight.

In this task, we have an array of numbers and we want to compute the sum of its values.

We have a variable ,sum, that will store the value of the sum of numbers from the array.

We also have a variable ,counter, which we will use to track the number of iterations of the while loop.

Step 1: Create a while loop. The while loop should continue as long as the value of counter is less than the number of items in the array. (Hint: You can get that number by using the count property)

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.

Thanks!

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 {
  numbers[counter]
   sum += 0
}

2 Answers

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[counter]
  counter += 1

}

Why is this the answer? i didnt even think about adding a .count to it.

  • should i go back and rewatch a video ; i feel like the info isnt coming together ; clicking that i would reference back to a previous lesson. Obviously thats what im suppose to do

Some hints

  • So you don't create an infinite loop you will want to increase counter inside the loop
  • numbers[counter] gives you the values that you want to sum. Use this with sum +=