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iOS

Posted by Maya Holmes
Maya Holmes
3,319 Points

I need help while loops for swift basics 2.0

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

while sum <= counter{ print(sum + counter) sum++ sum = sum + numbers }

1 Answer

Safwat Shenouda
Safwat Shenouda
12,362 Points
Safwat Shenouda
Safwat Shenouda
12,362 Points

Here you go ..

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
}

Please let me know if you need explanation

tallonsimmons
tallonsimmons
1,164 Points

Okay, so, [counter] inside the while loop; why is that there, and what is it doing exactly?

Safwat Shenouda
Safwat Shenouda
12,362 Points

counter is doing two jobs: 1- it guides the iterations of the while loop: so while will keep looping as long as counter value is less than the numbers.count which is 7. Once counter is 7 , the looping stops. that's why we increase the counter by 1 inside the loop 2- it acts as an index for the array: We need to sum the values in the array , this means start with first number and each iteration we add the next number to it.. so we start with sum = 0 and then first iteration we add the value in the first location of the array which is numbers[0] , then next iteration we add the next one which is numbers[1] and so on. for this job we use counter the array index : numbers[counter] because counter start with 0 and ends with 6. it perfectly serve the purpose.