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

Joshua Neal
PLUS
Joshua Neal
Courses Plus Student 783 Points
Posted by Joshua Neal
Joshua Neal
Courses Plus Student 783 Points

Infinity While Loop My Loop Code is while counter < numbers.count{ sum += numbers[counter] }

My result is an infinity loop I don't understand whats going on.

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{
    sum += numbers[counter++]
}

1 Answer

andren
andren
28,558 Points
andren
andren
28,558 Points

In Swift 3 they dropped support for the ++ operator, so it is not a valid way of incrementing a variable.

You need to increment counter on a separate line. Like this:

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] // Just reference counter normally
    counter += 1 // Increment counter by using the += shorthand.
}