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

Posted by binod dhungana
binod dhungana
1,423 Points

Your code could not be compiled. Please click on "Preview" to view the compiler errors. i don't have preview option.

Challenge Task 2 of 2 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.

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 {
  print (numbers[counter])
  counter += 1
}

while counter < numbers.count {
var newValue = numbers[counter]
sum += newValue
sum ++
}

2 Answers

Matthew Connolly
seal-mask
.a{fill-rule:evenodd;}techdegree
Matthew Connolly
iOS Development Techdegree Student 11,595 Points
Matthew Connolly
.a{fill-rule:evenodd;}techdegree
Matthew Connolly
iOS Development Techdegree Student 11,595 Points

You are correct, a "Preview" button usually pops up but I do not see it when running your code. But I do believe your complier error is due to your use of sum++ which has been removed from Swift in favor of the sum += 1 syntax.

Also, your second while statement does not increment counter and, therefore, will run indefinitely because counter will always be less than numbers.count.

Think about combining your while statements:

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

while counter < numbers.count {
    // calculate sum

    // increment counter
}
binod dhungana
binod dhungana
1,423 Points

thank you for your help.....

Chris Stromberg
PLUS
Chris Stromberg
Courses Plus Student 13,389 Points
Chris Stromberg
Chris Stromberg
Courses Plus Student 13,389 Points

You have a lot of extra code in your answer. The challenge asked for just a few things, you added a print statement, and an extra while statement.

while counter < numbers.count {
  sum = numbers[counter] + sum
  counter += 1
}
binod dhungana
binod dhungana
1,423 Points

thanks Chris.......