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

Walker Kinne
Walker Kinne
902 Points
Posted by Walker Kinne
Walker Kinne
902 Points

Sum

Just curious why this code would fail?

If I pull into a playground I am able to get the sum perfectly

loops.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 += numbers[index]
counter += 1

}

3 Answers

andren
andren
28,558 Points
andren
andren
28,558 Points

The issue is that in this line:

sum += numbers[index]

You refer to a variable called index which does not exist. I'm assuming you meant to type counter instead. If you fix that typo then your code will work fine.

Matt Buckingham
Matt Buckingham
11,389 Points
Matt Buckingham
Matt Buckingham
11,389 Points

If you use counter instead of index it should pass! Index is not defined in your code!

Walker Kinne
Walker Kinne
902 Points
Walker Kinne
Walker Kinne
902 Points

Thanks for the help! It just clicked!