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

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

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!