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iOS

Posted by Chris Janowski
Chris Janowski
1,844 Points

Looping over ranges code challenge task 2 question.

I am trying to figure out how to appended the multiples of 6 from the constant multiple into the array.

var results: [Int] = []

for multiplier in 0...10 { results[multiplier] = (multiplier * 6) }

I thought this would work, but I am not sure why its not working. Help would be greatly appreciated.

2 Answers

Evan Demaris
Evan Demaris
64,262 Points

At a glance, you're not appending the results to the list; you're trying to replace a nonexistent index in an empty list with each multiple, instead. You're also starting your list at 0 instead of 1.

var results: [Int] = []
for multiplier in 1...10 {
    results.append(multiplier * 6)
}

Hope this helps!

Chris Janowski
Chris Janowski
1,844 Points

Thank you! I put 0...10 so that my array would start at index 0 . So when you append it will automatically go to the next index. Instead of modifying the same index multiple times.

Evan Demaris
Evan Demaris
64,262 Points

Actually, your original code would work if you first initialized the list with 10 blank numbers, started the multiplier at 1, then subtracted 1 from your multiplier index; that way, you aren't trying to access a nonexistent index, your index would start at 0, and you'd still have the 1...10 that the multiplier is looking for in this challenge. 

var results: [Int] = [0,0,0,0,0,0,0,0,0,0]

for multiplier in 1...10 {
    results[multiplier-1] = (multiplier * 6) 
}
Chris Janowski
Chris Janowski
1,844 Points
Chris Janowski
Chris Janowski
1,844 Points

Awesome thank you!

Thank you for explaining it, very helpful.