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iOS Swift 2.0 Collections and Control Flow Introduction to Collections Working with Arrays

Bummer code error, not sure why!

Coming back with an error and not sure why that is, any help would be much appreciated :)

// Enter your code below
var arrayOfInts = [4,5,6,7,8,9,10]
arrayOfInts += [13]
Michael Jones
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Michael Jones
Python Development Techdegree Graduate 38,552 Points

Hi Patrick,

The code you've written is correct it just they wanted you to add one number for each method. See below -

// Enter your code below
var arrayOfInts = [1,2,3,4,5,6]

Hope this helps. And keep up the good work!!

Thanks, Michael J

2 Answers

Hi Patrick,

Further to what Michael put, and he's right, the length of the array after the last challenge was expected to be two more than the first task. However, you used the append method with two parameters; Swift won't allow that. You can use += to add an array of any length to another array but the append method can only add one element at a time.

var array = [1, 2, 3]
var anotherArray = [4, 5, 6]
array.append(anotherArray) // fails - can't convert [Int] to Int
array += anotherArray // works fine
array.append(10)   // works fine
array.append(12, 13)  // Fails. Can't use (Int, Int) with append

I hope that helps.


oh yeah alright cheers