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iOS Swift Collections and Control Flow Control Flow With Loops For In Loops

Nicholas Moore
Nicholas Moore
1,117 Points

In this challenge, I am confused on what exactly the "multiplier" name is and does.

I understand what "for loops" do, but in this case I am very confused on what the question is asking. And what is the name in the loop?

loops.swift
// Enter your code below
var results: [Int] = []
for multiplier in 1...10 {
multiplier * 6
}
results.append(multiplier)

1 Answer

Simon Di Giovanni
Simon Di Giovanni
8,429 Points

Ok so, the word 'multiplier' is the name of a TEMPORARY constant that is created, that is used only in the 'for' loop.

For example, multiplier could be named 'bananas', and the result would be the same!

It's just a NAME given to the value that you are iterating through.

So basically, what happens is the loop starts at 1, and assigns 1 to 'multiplier'. It then goes into the loop and does your code, which is multiplier(which is 1) * 6.

Then the for loop has finished, so multiplier IS DELETED.

The loop then starts again! Multiplier becomes 2, then multiplier(which is 2) * 6.

It then keeps repeating this until it gets to the last value you've specified, which is 10.

Hopefully this makes sense. If it doesn't, please let me know.

Nicholas Moore
Nicholas Moore
1,117 Points

Yes ! Thank you that makes perfect sense. But then my code is not working. It is saying I have “multiplier” as an unresolved identifier, and same as the multiplication sign.

Simon Di Giovanni
Simon Di Giovanni
8,429 Points

Sorry for the late response!

Your ‘results.append(multiplier)’ is being called outside of the for loop. Remember - multiplier ONLY exists in the for loop!

What you could write, is this - results.append(multiplier * 6)

Making sure that it’s INSIDE the for loop