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

whats wrong

whats wrong with my code?

var arrayOfInts = [1,2,3,4,5,6]
arrayOfInts + [7] 
let value = arrayOfInts[5] 
arrayOfInts + [9] 
let value = arrayOfInts[4]

1 Answer

Charles Ganzen
Charles Ganzen
1,568 Points

Hi Ronald,

It looks like you've added the new Int of 7 without actually assigning it back to the array.

arrayOfInts + [7] doesn't actually assign your concatenation back to the array arrayOfInts. To achieve this you could do either of the following:

arrayOfInts = arrayOfInts + [7]
arrayOfInts += [7]

Hope that helps!