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iOS Swift Collections and Control Flow Control Flow With Loops Looping Over Ranges

Vladislav Kobyakov
Vladislav Kobyakov
9,439 Points

Out of range error.

So I've tried out the following code in Xcode playground but it didn't work.

var results: [Int] = []

for multiplier in 1...10{ results[multiplier] = multiplier * 6 }

It seems valid to me but the compiler says "fatal error. Out of range" Since it says "out of range" I somewhere try to refer to a non-existing element in the array. Why is it invalid? Am I allowed to use only "append" method in Swift in such case and not assigning a value directly to the pointed element?

2 Answers

Vladislav Kobyakov
Vladislav Kobyakov
9,439 Points

Nevermind, I see the error... Here's the valid code: var results: [Int] = []

for multiplier in 1...10{ results[multiplier-1] = multiplier * 6 }

for multiplier in 0...9{ results[multiplier] = multiplier * 6 }