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

Chase Grainger
Chase Grainger
4,830 Points

I have no idea how to do this.

Please help me solve this. Question is not very clear for beginners.

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 {
  counter += 1
  sum  += numbers - 1
}

1 Answer

The question asks you to find the sum of the numbers array. Inside the while loop, the counter is used as the index of the array, after adding the current array element numbers[counter] to sum, increment the counter by one to access the next element. Keep adding until counter index reaches the boundary of the array, that's why we have "counter < number.count" condition.

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[counter]
  counter += 1
}
Chase Grainger
Chase Grainger
4,830 Points

I get it now. Thank you so much. Apparently Treehouse doesn't like if I switch line 8 & 9 around, even though it works in swift playground.