While loop is going on forever

Question

The error says that the loop is going on forever. I thought that if the counters value is at 7 then it would stop, what am I doing wrong, please help!
```while.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
}
```

Steven Deutsch · Answer

Hey Jack Colosky, 
We have an array of numbers. We want to compute the total (sum) of all of the numbers inside that array. The sum starts out with an initial value of 0. We also have a counter variable with an initial value of 0.
Now we create a while loop. The loop will continue as long as the counter is less than the number of items in the numbers array.
Inside the body of this loop, we compute the sum of the numbers. First we take the previous sum value and then add the value of the number in the array to it. We get the number from the array using subscript syntax. Since arrays are zero based, and our counter starts off with a value of 0, using the counter to subscript the array will return us the first value in the array.
You can think of it like this. sum = sum + numbers[0]
After we perform this math, we increment the value of counter by 1. This loop then runs again, but this time using the value of 1 for the counter to retrieve the number from the array.
This process will continue until the while loop's condition evaluates to false.
```Swift
let numbers = [2,8,1,16,4,3,9]
var sum = 0
var counter = 0
// Enter your code below
while counter < numbers.count {
    sum = sum + numbers[counter]
    counter++
}
```
Good Luck

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Jack Colosky

Jack Colosky

While loop is going on forever

Jack Colosky

Jack Colosky

1 Answer

Steven Deutsch

Steven Deutsch