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

Posted by aaron du
aaron du
5,946 Points

i don't get this question

i don't get this question, can someone help me, please??

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
    counter += numbers
    sum += counter
}

1 Answer

Chris Stromberg
PLUS
Chris Stromberg
Courses Plus Student 13,389 Points
Chris Stromberg
Chris Stromberg
Courses Plus Student 13,389 Points

Your code is below. There are several errors. It may help to try the challenges in the xcode playground before submitting your answer to the challege.

while counter <= numbers.count{
    counter += 1
    counter += numbers
    sum += counter
}

The errors.....

This will put your index out of range for the array. 

while counter <= numbers.count

Your code within the while loop does not add up each integer in the array. You need to have a reference to the numbers array and use the counter as the index for the array. Take the number that is at that index in the array and add it to the sum variable. Then you advance the counter by adding 1 to it. Look at my code and compare to yours.

counter += 1
    counter += numbers
    sum += counter

The correct code is below. 

while counter < numbers.count {

    sum += numbers[counter]
    counter += 1
}