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

This loop got me all loopy

In this task, we have an array of numbers and we want to compute the sum of its values.

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)

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

// Enter your code below

1 Answer

Richard Lambert
Richard Lambert
Courses Plus Student 7,180 Points

Hello mate,

The size of the numbers array is accessible from its .count property. To iterate over each element of numbers, the while statement's conditional expression should evaluate to true so long as counter is less than numbers.count, and counter should be incremented by one from within the statement's body. This incrementation should occur after any expression that accesses numbers using the counter value.

let numbers = [2,8,1,16,4,3,9]
var sum = 0
var counter = 0
while counter < numbers.count {
    // add numbers[counter] to sum
    counter += 1

Hope this helps