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

The while loop challenge 1 of 2

i do not understand this challenge can you guys explain it to me please i already re watch the chapter but still do not get it. thank you

This one might be a bit tricky so let's take it in steps. We have an array of numbers, nothing tricky, you've seen this before. What we want is to compute the sum of the numbers in the array. To do this we're going to use a while loop.

We have a variable ,sum, that will store the value of the sum of numbers from the array.

We also have a variable ,counter, which we will use to track the number of iterations of the while loop.

Step 1: Create a while loop. The while loop should continue as long as the value of counter is less than the number of items in the array. (Hint: You can get that number by using the count property)

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

// Enter your code below

Here is how to solve it: while counter < numbers.count { sum += numbers[counter] counter++

}

while will keep looping until the loop condition is not satisfied anymore. You start with counter initial value 0 , then keep increasing it each loop until is not any more less than the numbers.count value which is in this case 7. each loop you add the number in the current array position to the sum.

1 Answer

Thank you for you help Safwat Shenoudav =)