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

Lana Wong
Lana Wong
3,968 Points

How do you retrieve values and add it in the variable sum?

Instructions

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.

How do I do this?

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

// Enter your code below

counter = 0
while counter < numbers.count{
counter += 1
for newValue in numbers{
sum = sum + newValue
}

}

1 Answer

You can do this by simply using the while loop. Hope this helps :)

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 += 1
}