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

Joe Nelson
Joe Nelson
1,331 Points
Posted by Joe Nelson
Joe Nelson
1,331 Points

In need of help!

"Now that we have the while loop set up, it's time to compute the sum! Using the value of counter as an index value, retrieve each value from the array and add it to the value of sum.

For example: sum = sum + newValue. Or you could use the compound addition operator sum += newValue where newValue is the value retrieved from the array."

can someone help explain what I need to do for this task?

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 {
    print(numbers[counter])
    counter++
}

1 Answer

Tobias Helmrich
Tobias Helmrich
31,602 Points
Tobias Helmrich
Tobias Helmrich
31,602 Points

Hey there Joe,

good job until here! In the second task you can remove your print statement and instead of printing it out just add every item of the numbers array to the sum variable. To do that you can use the compound assignment operator += and with it you can add every number at the index of counter's value.

Like so:

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++
}

I hope that helps, if you have further questions just ask! :)

Joe Nelson
Joe Nelson
1,331 Points
Joe Nelson
Joe Nelson
1,331 Points

Thanks for the help Tobias!

I realize now I didn't even need the print statement at all. Im not sure why I thought that was part of the while loop.

Thanks again!