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

Ranak Bansal
Ranak Bansal
1,207 Points

While Loops Help

What is an "index value," and what does it mean when it says, "Using the value of counter as an index value, retrieve each value from the array and add it to the value of sum."

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

}

1 Answer

Hi there,

The index value is the nth position of an element in an array. Each element in the array you have been given can be accessed by using an index number. These start counting at zero such that the first element in the array is accessed with zero using square brackets, like so: numbers[0].

You have a counter variable, called counter, which starts as zero and is incremented as the loop runs. You can use that to access each element in turn, such as: numbers[counter].

To complete the challenge you need to add into sum every value stored in each numbers[counter].

I hope that helps.

Steve.