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iOS Swift 2.0 Collections and Control Flow Control Flow With Loops Working with Loops

What's wrong with my code?

Trying to complete this challenge...I just don't know how!

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

// Enter your code below


while counter <= numbers.count { 

var newValue = numbers[counter]

sum = sum + newValue

counter++

}

2 Answers

Chase Marchione
Chase Marchione
155,055 Points

Hi Vic,

  • We want to have the while loop run while counter is less than numbers.count, rather than less than or equal to (if the values are equal, that would mean that we don't have another value left to add to the sum.)

  • I recommend removing the newValue variable altogether (though if we did keep the newValue variable, we'd want to write the declaration of it outside of the while loop: otherwise, the compiler would attempt to redeclare newValue every time that the loop is run), since we can accomplish what we want to do without that extra variable (and therefore, extra lines of code.)

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

Hope this helps!

Thank you so much, really appreciate it.