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John Robinson III
2,388 PointsI need help
I don't understand this
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}
while counter < numbers.count
{ counter += 1
sum = sum + numbers[counter-1]
}
2 Answers
tromben98
13,273 PointsHi here is the solution:
Using the value of counter as an index value, retrieve each value from the array and add it to the value of sum.
let numbers = [2,8,1,16,4,3,9]
var sum = 0
var counter = 0
// Enter your code below
while counter < numbers.count
{
sum += numbers[counter]
counter += 1
}
Brandon Mahoney
iOS Development with Swift Techdegree Graduate 30,149 PointsYou want to increment counter last. On the first time through counter is 0 so 2 is added to sum and then counter is incremented and becomes 1. Then on the second pass through 8 is added to sum giving sum the total of 10 and so on. This is because counter is equal to 1 and the number 8 is in the 1 spot in the numbers array.
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 += 1
}