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

Coding a while loop

This one might be a bit tricky so let's take it in steps. We have an array of numbers, nothing tricky, you've seen this before. What we want is to compute the sum of the numbers in the array. To do this we're going to use a while loop.

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)

They are asking for stuff they don't cover in their lectures. The first section was ok but section 2 is hard without enough information. Thinking of dropping it altogether!

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

// Enter your code below

2 Answers

Hi David,

There is a good example of the while loop within the video, this matched together with the hint on using the count property of the array to get the length of the array should provide you with everything you need to complete the challenge.

Don't be disheartened you are nearly at the end of that course, stick with it and it will click.

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

// Enter your code below
while(counter < numbers.count) {
  counter++;
 }

Hope that helps

KB :octopus:

Christopher Albrecht
PLUS
Christopher Albrecht
Courses Plus Student 1,788 Points

I'll second Dave's frustration. It looks like Swift 3.0 is deprecating some of these commands. But beyond that, this video did a pretty horrendous job of setting up context and providing a bigger picture. If future videos don't improve, I'm going to try out other online coding options. Whomever set up this curriculum did a bad job of providing an overall narrative and explaining the "whys" of what we are doing.