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iOS Swift Collections and Control Flow Introduction to Collections Working With Arrays

Since the array is mutable, let's add two more values to the existing array. There are two ways we can add items to an a

Since the array is mutable, let's add two more values to the existing array. There are two ways we can add items to an array and I want you to give both a try. First, add one item to the array using the append method.

Remember: We invoke methods on an array using a period or dot. After the dot we write out the method name and a value to append in parentheses following the name.

Next, add another item to the array by concatenating an array. When concatenating, assign the results of the expression back to arrayOfInts.

array.swift
var arrayOfInts = (1,2,3,4,5,6)
arrayOfInts.append(7)
arrayOfInts.append(8)
arrayOfInts + (7) + (8)

4 Answers

The wording of the question is really confusing. It turns out it just wants you to add one int for the append and one int for the concatenation

var arrayOfInts = [1,2,3,4,5,6]

arrayOfInts.append(7)

arrayOfInts += [8]

Moritz Lang

this works. Xcode places the values of () in the code when you blow the auto function to work. var arrayOfInts = [1, 2, 3, 4, 5, 6] arrayOfInts.append(7) arrayOfInts += [8]

Moritz Lang
Moritz Lang
25,909 Points

Hey, you should rewatch the video. In Swift you declare an array with [] and not (). Also concatinating an array means arrayOfInts += [7, 8].

Don't second guess yourselves!

It turns out that they only want one value per added array.

Like such:

arrayOfInts.append(x)

arrayOfInts += [x]