Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

iOS Swift Collections and Control Flow Control Flow With Loops While and Repeat While

Posted by studentswift
studentswift
9,476 Points

I need help to understand a problem.

I solved following problem, but I frankly don’t understand why "counter +=1" is part of the solution. Is it because it moves from one number to another?

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

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

1 Answer

Victor Mercier
Victor Mercier
14,667 Points

Hi, the counter has basically two purposes : The first one is that make sure that you are not creating an endless loop by saying you want run the loop as long as counter is smaller than the length of the number array, so by increasing the counter, the loop will stop to run a day.

The second purpose is that you want add different items in the array, so by increasing the counter you are accessing a different item in the array every time.

If that helped, you can mark as best answer to indicates that your issue is resolved!