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

whats the problem

whats wrong with my while loop ?

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

// Enter your code below
while numbers {
continue(counter)
counter += 6
}

1 Answer

Alex Koumparos
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.a{fill-rule:evenodd;}techdegree
Alex Koumparos
Python Development Techdegree Student 36,887 Points

Hi Ronald,

In Swift, the condition for a while loop must be a Bool (or an expression that evaluates to a Bool). Your condition numbers is an array. Typically you want to compare something to something else (and that comparison will evaluate to a Bool). For example:

while a < b {
    print("I'm in a loop")

The challenge instructions gives you a hint that you might want to compare the count property on numbers to something.

Once inside the loop, you need to modify a variable so that once the loop has run the correct number of times, it will terminate.

In your loop you are increasing counter by 6. However, your while conditional never compares anything to counter so changing the value of counter doesn't do anything. Even if it did, I don't think you'd want to increase it by 6 every time you go through the loop.

Hope these hints point you in the right direction. Let me know if you are still stuck after trying the changes I've described.

Cheers

Alex