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iOS Swift Basics (retired) Control Flow While and Do-While Loop

kirstie perez
kirstie perez
312 Points
Posted by kirstie perez
kirstie perez
312 Points

While loop not working. Please help.

Guys, this code isn't working for some reason. Please answer if you see anything wrong, cause' i can't see anything wrong. Thanks! :)

while_loops.swift 
let numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
var index = 0
while index < numbers.count{
    println(numbers.count[index])
    ++index
}

4 Answers

Dennis Parussini
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Dennis Parussini
Treehouse Project Reviewer
Dennis Parussini
.a{fill-rule:evenodd;}techdegree seal-36
Dennis Parussini
Treehouse Project Reviewer

Yes, it should be index++. ++index increments the index before the check for index < numbers.count. This way your array would be out of range.

arnavthecoder
arnavthecoder
3,453 Points
arnavthecoder
arnavthecoder
3,453 Points

Hello,

I believe it should be index++.

Also can I see the error?

Walter Recinos
Walter Recinos
2,077 Points
Walter Recinos
Walter Recinos
2,077 Points

Like the instructor said: when you write ++index in a loop that starts conditioning the "index" value to be less than numbers.count, there is a point where index value = 10 and then turns into 11 inside the loop... which is not supposed to happen since 11 is not lower than numbers.count..

English is not my main language so i apologize if my answer was not clear.

kirstie perez
kirstie perez
312 Points
kirstie perez
kirstie perez
312 Points

Thanks to all who answered. You helped a lot.

arnavthecoder
arnavthecoder
3,453 Points

No problem