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

Absolutely lost with a code challenge dealing with loops. Can someone help me with the code for task 1 and 2.

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)

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 += numbers[counter]
      counter++
}

1 Answer

andren
andren
28,558 Points

The problem is "counter++", in Swift 3 they dropped support for the ++ and -- operators, using them is no longer accepted, and will lead your code to crash. If you replace it with some other incrementing code like "+= 1" like this:

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
}

Then your solution will pass since the rest of your code is perfectly fine.