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Now that we have the while loop set up, it's time to compute the sum! Using the value of counter as an index value, retrieve each value from the array and add it to the value of sum.

For example: sum = sum + newValue. Or you could use the compound addition operator sum += newValue where newValue is the value retrieved from the array.

while.swift
```let numbers = [2,8,1,16,4,3,9]
var sum = 0
var index = 0

while index += numbers  {
print([index])
index++
}
``` So what we are trying to do here in task 1 is set up a while loop. The way the english of the task reads helps you understand how. They say "while counter is less than the length of the array" and hint you can use the count method on the array to calculate that.

The second task tells us to add each array item to the sum variable. Again it hints we can use the counter as the index number for the array item.

So then your code would look something like this.

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