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

Ricardo Gonzalez
Ricardo Gonzalez
2,286 Points

How do I setup my code.

Don't know how to retrieve the value?

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

while counter < 1 {

counter++
}

2 Answers

Ricardo, it's usually not a good idea to hard-code a number for a loop limit, in case the array gets replaced by a numbers array with more or fewer elements. You use the counter variable to keep track of how many times the loop has run, and you set it up so that it can be used in subscript notation to access the individual elements in the loop:

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

while counter < numbers.count {
    sum += numbers[counter]
    counter++
}
print(sum)
Owen Ou
PLUS
Owen Ou
Courses Plus Student 5,542 Points
let numbers = [2,8,1,16,4,3,9]
var sum = 0
var counter = 0

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

I think this may be a little bit easier to understand.