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

Posted by Terry Hearn
Terry Hearn
Courses Plus Student 429 Points

I am having issues computing the sum please help but i want to understand how you go the answer so i know how to do sums

how to code this sum i am confused and really want to understand so i can compute sums moving forward.Thanks

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 { 
sum = counter + numbers 
counter++
}

2 Answers

jcorum
jcorum
71,830 Points
jcorum
jcorum
71,830 Points

Very close. counter must be less than numbers.count, not less than or equal, and you need to use sum as an accumulator in order to add up the values. 

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

Note that sum = sum + numbers[counter] can also be written as sum += numbers[counter]

Either way, sum is totaling the values in the array.