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iOS Swift Collections and Control Flow Control Flow With Loops Working With Loops

Posted by Elizabeth Hernandez
Elizabeth Hernandez
1,207 Points

In code challenge, noted "preview" for compiler errors does not exist

In the code challenge step a simplified Swift Playground window is displayed. When "Check work" returns, "X Bummer!" the error requests user to "Please select preview to view the compiler error", but no such option (labeled "preview") exists in this window.

On top of that, when I run the code via an actual Swift Playground environment in Xcode, no error is returned. The code runs as expected.

Any ideas what's expected here?

loops.swift 
let numbers = [2,8,1,16,4,3,9]
var sum = 0
var counter = 0

// Enter your code below
while count

while counter < numbers.count {
    sum = numbers.reduce(0, +)
    counter += 1
}

1 Answer

Jeff McDivitt
Jeff McDivitt
23,970 Points
Jeff McDivitt
Jeff McDivitt
23,970 Points

No need to use reduce as the task does not ask for that

let numbers = [2,8,1,16,4,3,9]
var sum = 0
var counter = 0

// Enter your code below

while counter < numbers.count {

sum += numbers[counter]
counter += 1

}
Dennis Kovacich
Dennis Kovacich
476 Points

I had the same problem. I got past it when I realized I was using parentheses instead of brackets for the array subscript. But the "Preview" tab that was present in earlier code challenges is not there on this one.