compute inside loop

Question

I don't understand how to compute inside my loop... 
I got this far in the challenge: 
let numbers = [2,8,1,16,4,3,9]
var sum = 0
var counter = 0
// Enter your code below
while sum <= 7 { print(sum)
                sum++
}
thanks for your help
```while.swift
let numbers = [2,8,1,16,4,3,9]
var sum = 0
var counter = 0
// Enter your code below
while sum <= 7 { print(sum)
                sum++
}
```

Brendan Whiting · Answer

A few things:
1) you're using sum where you should be using counter.  The purpose of the variable counter is to count how many times you've been around the loop.  
2) You should stop your loop when counter is less than or equal to 6, or less than 7.  The way it is right now you're going to do the loop too many times, which will end up with an error because you'll be going past the end of your array.
3) Inside the curly braces of your loop, before you increment your counter up, you should put sum += numbers[counter].  This is going to use the counter variable as the index of the array, starting with 0, and it will add each item in numbers into sum as it goes through the loop.
Here's the code:
```Swift
while counter <= 6 {
    sum += numbers[counter]
    counter++
}
```

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Raphael Reiter

Raphael Reiter

compute inside loop

1 Answer

Brendan Whiting

Brendan Whiting