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iOS Swift Basics (retired) Collections Modifying an Array

Posted by Tiffany Kang
Tiffany Kang
654 Points

There shows an error when I try to compete the 3rd task in this challenge.

Although in the 3rd task I put todo.insert("Learn iOS", atIndex: 1) it says that todo has the wrong value in it. When I tried using the preview, nothing shows up.

arrays.swift 
var todo = ["Learn Swift", "Build App", "Deploy App"]
todo.append("Debug App")
todo.append("Fix Bugs")
todo.removeAtIndex(1)
let item = todo.removeAtIndex(1)
todo.insert("Learn iOS", atIndex: 1)

1 Answer

Vittorio Somaschini
Vittorio Somaschini
33,371 Points
Vittorio Somaschini
Vittorio Somaschini
33,371 Points

Hello Tiffany.

The problem relates to task 2/3 of the exercise:

That part asks you to remove the third item and assign it to a constant named item. Instead of the 2 lines you wrote:

todo.removeAtIndex(1)
let item = todo.removeAtIndex(1)

You should use this 1-line code:

let item = todo.removeAtIndex(2)

This is because you actually did what the 2/3 exercise asked (so you managed to pass that challenge) but you removed 2 items (the first at index1) and then the second at the new index 1 after removing the first item. This resulted into a problem with challenge 3/3.

Let me know if it is all clear.

Vittorio