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

Posted by jenko
jenko
8,562 Points

fatal error: Index out of range, Counter won't work

This produces an error in Xcode 9, fatal error: Index out of range.

Which is odd because at this point counter should be 0 until I tell it to add 1.

This happens no matter which method I use,

  • sum += numbers[counter]
  • sum = sum + numbers[counter]

Is this broken or something xCode won't allow ?

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

// Enter your code below

while counter <= numbers.count {
  sum = sum + numbers[counter]
  counter += 1
}

1 Answer

jenko
jenko
8,562 Points

Silly me, wrong condition.

while counter < numbers.count {
  sum = sum + numbers[counter]
  counter += 1
}