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iOS Swift Collections and Control Flow Control Flow With Loops Working With Loops

Ranak Bansal
Ranak Bansal
1,207 Points
Posted by Ranak Bansal
Ranak Bansal
1,207 Points

While loops code challenge

I don't understand what I am doing wrong, it just says bummer when I type it in.

loops.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
      sum = sum + numbers[counter]    
}

2 Answers

Matthew Long
Matthew Long
28,407 Points
Matthew Long
Matthew Long
28,407 Points

You're very close! Looks like you're incrementing the counter before you use the counter as the index in the numbers array. So place that last and you're good!

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

while counter < numbers.count {
  sum += numbers[counter]
  counter += 1
}
Ranak Bansal
Ranak Bansal
1,207 Points
Ranak Bansal
Ranak Bansal
1,207 Points

I did exactly as you said, but I still got the error, then I copy and pasted your code but still got the error. Does it make a difference that I completed this challenge a while ago but I just wanted to review it, so I did it again?

Matthew Long
Matthew Long
28,407 Points
Matthew Long
Matthew Long
28,407 Points

You can redo challenges as often as you want. If you copy my code the challenge will pass. Make sure there's nothing else in the window. Maybe try reloading the page too.