Code is incorrect but does not give reason

Question

Any help would be appreciated

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 1 · 2017-07-16T13:24:09Z

July 16, 2017 1:24pm

Hi there! You're correct that it's not giving any message besides "Bummer!". But if you run this in an Xcode playground you'll see that it's encountering an error from which it cannot recover. This is because you are attempting to access an index of the array that doesn't exist. But, if I delete just one character from your code, your code passes!

Here you've written:

while counter <= numbers.count {

But that should be

while counter < numbers.count {

The numbers array contains seven elements, which means that numbers.count is equal to 7. But you cannot access numbers[7] as the last element of the array is at numbers[6]. On the last iteration of the loop counter will be 7 and less than or equal to numbers.count. Because that's true it will run the code block which tries to access numbers[7]. So we need to remove the "or equal to" part.

Hope this clarifies things!

edited to fix clunky wording

Answer 2 · 2017-07-16T13:24:49Z

July 16, 2017 1:24pm

Hey Aaron,

It looks like you have mistakenly added in the 'less than or equal too' (<=) operator to your loop.

Just the less than operator (<) is required in order to pass the task, as the code challenges can be very particular in what they are looking for.

Good luck!

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Aaron Schokman

Aaron Schokman

Code is incorrect but does not give reason

2 Answers

Jennifer Nordell

Jennifer Nordell

Jordan Barr

Jordan Barr