Understanding why this is the solution

Question

OK so for this challenge I got this solution that allowed me to pass but I need a little more breakdown on why it was the solution.
while counter < numbers.count {
sum += numbers[counter]
counter++
}
```while.swift
let numbers = [2,8,1,16,4,3,9]
var sum = 0
var counter = 0
// Enter your code below
```

andren · Accepted Answer

The challenge asks you to compute the sum of the numbers in the array, to get sum of the numbers you simply need to add all of them together. And that is what the code does.
objectivec
          while counter < numbers.count

Here you are saying that the loop should go while the counter variable is less than the number of items in the numbers array, which results in the loop running once for every number, due to the counter starting at 0.
objectivec
          sum += numbers[counter]

Here you are taking the sum variable and adding one of the numbers from the number array to it, the first time though the loop the first number from the array will be added, the second time though the second number and so on, this is due to the fact that you are using the counter variable as the index for the array.
objectivec
          counter++

Then finally you are adding one to the counter, this is needed both to ensure that the loop eventually ends and so that during the next loop you will get the next number out of the numbers array.
At the end of the loop the sum array will be equal to all of the numbers of the numbers array added together, which is what a sum is.

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Larry Taylor Jr

Larry Taylor Jr

Understanding why this is the solution

1 Answer

andren

andren

Larry Taylor Jr

Larry Taylor Jr