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iOS Swift 2.0 Collections and Control Flow Control Flow With Loops Working with Loops

Mark Carrel
Mark Carrel
9,873 Points
Posted by Mark Carrel
Mark Carrel
9,873 Points

how do i make a while loop

i forgot the syntax please send help

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

// Enter your code below

while counter < numbers.length

1 Answer

jcorum
jcorum
71,830 Points
jcorum
jcorum
71,830 Points

Here it is, step-by-step:

//start with **while() {**, then put a boolean expression inside the parentheses
//the loop will run as long as the condition is true
while(counter < numbers.count) {
  //add up the numbers in the numbers array
  sum += numbers[counter]
  //increment the loop counter 
  counter++
  //close the code block
}

In this challenge they want the loop to sum up the numbers in the array, so the condition needs to be written so the the loop will run once for each number. Making the condition counter < numbers.count will ensure that the loop gets numbers[0], numbers[1], ..., numbers[6], and then stop.